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Cisco's LEAP Authentication Cracked

CowboyNeal posted more than 9 years ago | from the cisco's-bad-week dept.

Wireless Networking 162

mtrisk writes "Just a day after Cisco released a security warning about its WLSE access point management tool, a tool to crack wi-fi networks using LEAP authentication has been released, reports Wi-Fi Networking News. The tool, called Asleap and developed by Beyond-Security, actively de-authenticates users, sniffs the network when the user re-auntheticates, and performs an offline dictionary attack upon the password."

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162 comments

Not Cisco's week (5, Informative)

Novanix (656269) | more than 9 years ago | (#8824760)

Man to say this isn't Cisco's week would be an understatement. It can also read saved libpcap and airopeek captures. It also can save the required data only to a file for later processing so you can use it on a Palm or WinCE device. Also, for those who just want to get started: Windows Binary [slashdot.org] | Source [slashdot.org] .

Re:Not Cisco's week (5, Informative)

nova2 (765982) | more than 9 years ago | (#8824775)

Better links: Windows [sourceforge.net] | Source [sourceforge.net]

Re:Not Cisco's week (0)

Anonymous Coward | more than 9 years ago | (#8824781)

Working URLs:

Windows Binary [sourceforge.net]
Source [sourceforge.net] .

Re:Not Cisco's week (4, Interesting)

Shakrai (717556) | more than 9 years ago | (#8824891)

Man to say this isn't Cisco's week would be an understatement. It can also read saved libpcap and airopeek captures

Yeah it's been a bad week for Cisco but they aren't Microsoft. They won't ignore these problems. You'll see firmware updates to fix the password problem in a week tops (if it isn't already out). I suspect you'll also see an update to address the LEAP issues.

The only reason to buy Cisco after all (in my experience -- I'm sure the detractors will speak up the minute I click post) is for the support.

I recall a strange off the wall problem I had using an ISDN line card in a 2600 series router a couple of years back. The line card wouldn't co-exist nicely with the 56k DSU/CSU line card in the other slot. After a few days the ISDN interface would choke and die and the router would need to be rebooted.

After working with our vendor's (Ingram Micro) Cisco support group and trying about a million different IOS upgrades they referenced us to Cisco -- the Cisco that we didn't even have a support contract with. They actually flew somebody out (we are on the East Coast) to look at the problem and released a specific IOS upgrade to address that issue once they confirmed it.

Do you think Microsoft would do that for the small time Insurance Agency with one large router (and a couple of smaller ones in our remote offices)? A lousy $6,000 router at that (money for us -- pocket change for Cisco). That's support and that's the reason why I will continue to buy Cisco products even if they are insanely overpriced.

Compare apples to oranges (-1, Redundant)

Anonymous Coward | more than 9 years ago | (#8825039)

There is a VAST difference between upgrading a router's firmware and changing code that is used by 0.5 billion people in millions of different ways. Get some perspective.

Re:Compare apples to oranges (1)

O2n (325189) | more than 9 years ago | (#8825492)

There is a VAST difference
Yes, it's the difference between fscking 300 milion Joe's who cannot sue you and don't really know the difference between a CPU and an operating system, and trying not to piss off big $$$ companies which can, eventually, sue. Microsoft is also helpful towards big $$$, rest assured.

Re:Not Cisco's week (4, Insightful)

dave_t_brown (447547) | more than 9 years ago | (#8825134)

Yeah it's been a bad week for Cisco but they aren't Microsoft. They won't ignore these problems. You'll see firmware updates to fix the password problem in a week tops (if it isn't already out). I suspect you'll also see an update to address the LEAP issues.

Except that they've known about this problem for months, and the security flaw is not entirely inherent in the protocol. Forcing users to choose strong passwords will provide significantly more protection to a "LEAP-protected" networks than any patch that Cisco could issue for LEAP.

I am entirely unenlightened on EAP-FAST, Cisco's replacement for LEAP, but I'm pretty sure it would be a significant deployment effort for IT to upgrade both the infrastructure and the client devices.

Re:Not Cisco's week (4, Interesting)

JackAsh (80274) | more than 9 years ago | (#8825152)

Yeah it's been a bad week for Cisco but they aren't Microsoft. They won't ignore these problems. You'll see firmware updates to fix the password problem in a week tops (if it isn't already out). I suspect you'll also see an update to address the LEAP issues.

Read the article - the LEAP problem was reported to them in AUGUST 2003.

I agree they are not a Microsoft, and they are generally much more responsive, but how would you feel if you had over the past six months implemented a major, wonderful, well protected Cisco LEAP wireless network? Only to receive the news that "yeah, we kinda knew since August our security sucked" (for the record, I am NOT in that situation, but LEAP was a contender for our upcoming wi-fi implementation).

Honestly, Bruce Schneier was recently saying that it's no longer about the crypto, as anyone can do strong crypto these days. It's about the factors around it, like usernames and passwords, physical security, but most of all, implementation. You'd think that something which was hailed at the time as the solution to the broken WEP protocol would be partially secure... Ugh. Now I'm just ranting.

-Jack Ash

Re:Not Cisco's week (3, Informative)

ca1v1n (135902) | more than 9 years ago | (#8825445)

They've known for a long time that LEAP is inherently flawed, and no patch can fix it. That said, it's a hell of a lot simpler to deploy than more secure things like EAP-TLS. This attack still requires an offline brute force decryption attempt. Granted, it may be a highly accelerated brute force decryption attempt, but if you don't allow your users to use passwords that are vulnerable to dictionary attacks, LEAP is Good Enough for many purposes.

Re:Not Cisco's week (1)

pVoid (607584) | more than 9 years ago | (#8825343)

Are you somehow comparing code complexity of router firmware to that of an OS? Because if you are, that's just absurd.

The reason they flew someone out is probably because they wanted to confirm the situation... it is in their best interest after all.

The reason why Microsoft doesn't fly people out isn't because they don't care, it's because a) you're dealing with software (not firmware) which can submit bug reports, b) reproducing the problem on their servers will most likely work (software is generally platorm/location independant enough to allow for this) c) broken firmware on a router kind of obviously means you likely won't be able to access the firmware remotely.

Don't even get me started on the support microsoft *does* give you when you actually need it (as opposed to when you're a dick-head newbie sysadmin who doesn't know how to setup an exchange server).

If it makes you happy though, wail on Microsoft all you want. We'll (linux/microsoft/mac) users will be rolling our eyes at you while you try and run your desktop using Cisco firmware.

IANAT(roll)

Re:Not Cisco's week (1)

TheCrazyFinn (539383) | more than 9 years ago | (#8825627)

IOS is an OS. It's quite router-specific, but it is an OS nonetheless. As is JunOS on Junipers (Which is FreeBSD based).

Even many dinky little routers actually run Linux as their OS.

Re:Not Cisco's week (1)

Florian Weimer (88405) | more than 9 years ago | (#8825472)

Yeah it's been a bad week for Cisco but they aren't Microsoft. They won't ignore these problems.

Not quite true. Their IPsec extension called XAUTH has got the same problems, and and these have been ignored for years:

http://www.ima.umn.edu/~pliam/xauth/

There's a recent rediscovery of the problem archived at: http://www.securityfocus.com/archive/1/347351

The only reason to buy Cisco after all [...] is for the support.

Exactly, and that's why it's sometimes so painful to be a Cisco customer. You have to buy more of their products, or you will lose support guarantees for existing products. And you need these guarantees if you are implementing highly experimental technologies such as QoS and VoIP on production networks, or it's your fault if things break (even if it's an IOS bug).

At least hardly anybody has Microsoft support contracts, so using different products where it makes sense is often a very desirable option because you can't lose that much.

Insight appreciated? (5, Interesting)

monstroyer (748389) | more than 9 years ago | (#8824772)

As a small business, i use a Linksys wireless router. Cisco now owns Linksys. Can anyone alleviate my "phears" and tell me that this vulnerability is more for the hardware found in big companies like Bell Canada, and not my WEP 64 wireless? I'd really appreciate a summary of what all the fuss is about and how it affects people who don't run mega corps. Thanks.

Re:Insight appreciated? (4, Informative)

rusty0101 (565565) | more than 9 years ago | (#8824805)

Not sure I can alleviate all your concerns, however...

The easiest way to see if you are affected by this issue is to get the model number of your access point, and go to the Linksys website. See what capabilities your AP has, and if the AP supports the LEAP authentication protocol.

If it does not, you are probably immune to this particular disorder. Beyond that I would say do not manage your AP over the wifi connection, without another encryption, and if possible disable login to the AP from the Internet. Beyond that I would recomend getting a good book on WiFi security, some have been reviewed here, though how good they are, I can't really judge.

-Rusty

Re:Insight appreciated? (0)

Anonymous Coward | more than 9 years ago | (#8825352)

Just so no readers are confused with what rusty0101 posted:

Running a Linksys AP with that doesn't have LEAP, and also has no extra firewall, and no SSH VPNs is as bad or worse than using an access point that uses compromised LEAP.

You really need to have SOME solution to deal with the inherent insecurity of wireless, and if it's not a LEAP (that'll hopefully be upgraded soon), it should be an SSH VPN or a good firewall with a good network topology, or something along those lines (as rusty0101 rightly pointed out. Just that readers shouldn't think that the take-home message is "if you don't have LEAP, you're good").

Re:Insight appreciated? (5, Informative)

Anonymous Coward | more than 9 years ago | (#8824809)

Your WEP 64 is already trivial to defeat with sufficient captured data (numbers fail me at the moment.. though something tells me that it may be in the many hundreds of megs captured).

Moreso if your router is older and produces the 'weak' packets that programs like Kismet detect (in which case, hundreds of megs becomes hundreds of kilobytes :-P )

Re:Insight appreciated? (1)

tietokone-olmi (26595) | more than 9 years ago | (#8825109)

Yes, the number is in the hundreds of megabytes. Typically, to crack a weakly-keyed wireless network you need to see about two gigabytes' worth of data, though the margin of error for this number is rather large since you'll be looking for packets with weak generated keys, and the occurrence of those is somewhat random. Could be more, could be less.

The nice thing is that you don't need to capture and save the encrypted frames. The cracking clients merely need to see enough traffic, which means that you could even crack a wireless network with one of those D-Link CF WLAN cards and any old IPaq, if the network had enough traffic going through it while your batteries last ;-)

Re:Insight appreciated? (1)

merlin_jim (302773) | more than 9 years ago | (#8825770)

(numbers fail me at the moment.. though something tells me that it may be in the many hundreds of megs captured).

Any WEP implementation can be broken with about a million packets, so says the documentation for AirSnort.

Re:Insight appreciated? (5, Informative)

AKnightCowboy (608632) | more than 9 years ago | (#8824813)

Cisco now owns Linksys. Can anyone alleviate my "phears" and tell me that this vulnerability is more for the hardware found in big companies like Bell Canada, and not my WEP 64 wireless?

This is for Cisco wireless products (their Aironet series for example), not Linksys products. I'm sure they're still pretty seperate companies even though Linksys may be a wholly owned subsidiary. i.e. Linksys access points don't run IOS (hell, some run Linux). Plus, your Linksys box wouldn't support LEAP anyway. Now, the problem with you is that 64-bit WEP is already easy to crack with enough data so it's a thin veil of security, nothing more. Don't rely on it to encrypt your traffic! If you're doing anything that needs encryption then use higher layers like SSL or even IPSEC.

Re:Insight appreciated? (0)

Anonymous Coward | more than 9 years ago | (#8824930)

A recently acquired, wholly owned subsidiary of Hadden industries?

Re:Insight appreciated? (3, Informative)

Shakrai (717556) | more than 9 years ago | (#8824823)

As a small business, i use a Linksys wireless router. Cisco now owns Linksys. Can anyone alleviate my "phears" and tell me that this vulnerability is more for the hardware found in big companies like Bell Canada, and not my WEP 64 wireless? I'd really appreciate a summary of what all the fuss is about and how it affects people who don't run mega corps. Thanks.

I haven't seen any Linksys hardware that uses LEAP but I haven't bought or used any since Cisco bought them out -- not out of distrust or dislike of Cisco -- just haven't had the chance or reason to.

I have used LEAP before in the Aironet 350 series AP from Cisco. My hunch says that LEAP is still limited to the Aironet line (Linksys is more targetted at home users while Aironet is for Enterprises) but I could be wrong. In any case I wouldn't call your Linksys AP secure just because it doesn't support LEAP. There are other ways to break WEP/mac address protection that have been discussed here before.

I purposely leave an AP on my home network. I figure it's an easy out if I get busted for downloading mp3s or Windows source code ;)

Re:Insight appreciated? (1)

GigsVT (208848) | more than 9 years ago | (#8825141)

. I figure it's an easy out if I get busted for downloading mp3s or Windows source code ;)

Until they send Slashdot a subpoena to tie your posts to your IP.

Re:Insight appreciated? (5, Informative)

FauxPasIII (75900) | more than 9 years ago | (#8824826)

> hardware found in big companies like Bell Canada, and not my WEP 64 wireless

Correct; asleap won't crack your network. However, airsnort will.

http://airsnort.shmoo.com/

So far as I'm aware, there hasn't been a link-layer security protocol for wireless made yet that
hasn't been cracked. That's why I run ipsec.

Re:Insight appreciated? (2, Interesting)

iamwahoo2 (594922) | more than 9 years ago | (#8824904)

How much damage can be done if somebody cracks your WEP? I am not particularly worried if someone is using my connection as much as I am worried that someone will get my private information like credit card numbers. If I only use machines on the wired LAN to keep and transmit private data, does that protect me?

Re:Insight appreciated? (1)

Aaron England (681534) | more than 9 years ago | (#8824921)

Most websites provide an additonal level of encryption known as SSL to protect credit card transactions.

Re:Insight appreciated? (2, Interesting)

FauxPasIII (75900) | more than 9 years ago | (#8825050)

> How much damage can be done if somebody cracks your WEP?

If somebody breaks into your WEP, they can do anything that any machine on your LAN can do. That is, they can sniff your traffic, they can access any internal servers that use only IP address checking for security (NFS is commonly set up this way) and they can use your connection to the net. The latter is more serious than you might think; for instance, what if they launch a DDoS, port-scan a bank, or serve child pornography from your IP address?

Linksys (0, Troll)

Moderation abuser (184013) | more than 9 years ago | (#8824832)

Bin it now! Not because it's insecure, bin it cos it's crap.

BTW, if you're running standard WEP it's pretty easy to get into your network anyway.

Re:Insight appreciated? (2, Interesting)

ph4s3 (634087) | more than 9 years ago | (#8824898)

First of all, don't use WEP. Many many articles about it being broken have been written. At a minimum you should be running a linksys with at least v1.41 (1.42?) of the firmware and be using the WPA security.

If you're doing anything that needs real encryption, such as administering anything requiring strong passwords or doing financial transactions, you should be researching a VPN layer or something along those lines.

Along the same lines, this seems to open up a new service category... VPN service authentication... Allow you to get a secure link from wherever you are physically at back to the VPN point. Protect your packets from being sniffed (and usable) by wire or wireless. Anyone seen this type of thing? I've only seen server+client side implementation, never an auth service.

Re:Insight appreciated? (1)

Gerald (9696) | more than 9 years ago | (#8825113)

Does Linux support WPA yet?

Sorry... (1)

Svartalf (2997) | more than 9 years ago | (#8825011)

I can't alleviate your fears with regard to your wireless router.

While Cisco owns Linksys, they don't use LEAP on that device (LEAP is typically used in enterprise contexts for wireless access...). However, your WEP based device is actually every bit as vulnerable because WEP's been cracked for pretty much any number of bits and has been for some time. LEAP was being touted as the fix to the problem and Cisco was flogging it pretty heavily- we now know that LEAP's not any better than WEP in all practical use.

Re:Insight appreciated? (2, Informative)

Superfly_rh (639969) | more than 9 years ago | (#8825139)

As a small business, i use a Linksys wireless router. Cisco now owns Linksys. Can anyone alleviate my "phears" and tell me that this vulnerability is more for the hardware found in big companies like Bell Canada, and not my WEP 64 wireless? I'd really appreciate a summary of what all the fuss is about and how it affects people who don't run mega corps. Thanks.

The vulnerability is if you use 802.1X authentication with the LEAP protocol.

The Access Point doesn't have a security flaw in it, the LEAP protocol does. If you have a Radius server that is configured to do LEAP and you have a wireless supplicant that supports LEAP and a wireless card that works with that supplicant, then you can do LEAP.

It used to only be the Cisco cards that could do LEAP, but I've noticed that changing lately.

But, you have a 64 bit WEP network, probably not doing 802.1x. I'd worry about that. And the thing is, that's worse than having a network secured with the security flawed LEAP protocol. You have no authentication and probably no key rotation going on. WEP is known to be horribly flawed. With LEAP you at least has authentication (although proven to be crackable by an offline dictionary attack) and WEP key rotation.

At least try and upgrade to WPA-PSK, with TKIP or AES. WPA w/Radius and TKIP or AES is preferred though. Some people say to use VPN's instead. I don't like that idea much... but that's just me, it seems to work great for some people.

ding dong (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#8824773)

the witch is dead. let's all have natural unprotected sex. campus orgies we shall squash. hail thee, chickepox!

yes! (-1, Flamebait)

Anonymous Coward | more than 9 years ago | (#8824776)

keep the kiddies happy!

Re:yes! (0)

Anonymous Coward | more than 9 years ago | (#8825696)

Cisco -> Ci sco -> Ci SCO -> SCO
Civilian control monkey.

When it rains, it pours... (5, Funny)

bfg9000 (726447) | more than 9 years ago | (#8824780)

What are these guys, the Microsoft of hardware?

Re:When it rains, it pours... (5, Funny)

PoopJuggler (688445) | more than 9 years ago | (#8824793)

Wouldnt that make them Microhard?

Re:When it rains, it pours... (1)

bfg9000 (726447) | more than 9 years ago | (#8824817)

I know there's a joke in there somewhere....

Re:When it rains, it pours... (1)

FreakyGeeky (23009) | more than 9 years ago | (#8825368)

Yeah there is, it's "the joke is in your hand."

Re:When it rains, it pours... (1)

tarballedtux (770160) | more than 9 years ago | (#8824815)

Can't we accept some problems with EVERY piece of software or hardware. At least they tried to make a product to make up for existing wireless security.

Crypto subsystems are notoriously difficult... (5, Interesting)

Svartalf (2997) | more than 9 years ago | (#8824836)

It's WHY you really, really ought to have a cryptologist design your subsystems if at all possible. If it's not possible, you need to have them AUDIT it at the very least. Suffice it to say, each and every one of the wireless designs so far seem to be fairly flawed- and I don't believe that a single one was designed by or audited by a competent cryptographer (Someone like Schneier comes immediately to mind- never mind how expensive this sort of person will be for you with the design work or an audit, the embarassment and increased liability for exploits on the system make it far, far more expensive to NOT hire them...).

I'm a fairly competant amateur- I know better than to assume anything I or anyone else that's not an SME produces in this arena is anything but vulnerable until proven otherwise.

Re:Crypto subsystems are notoriously difficult... (2, Insightful)

ballwall (629887) | more than 9 years ago | (#8824887)

There's another thing that I don't understand. Why use yet another method of encryption for wireless? Why can't the AP or router behind it be set up for a VPN. My company doesn't trust the internet, so it uses a VPN. If you don't trust your WIFI link, why not use a VPN?

This is the setup I have at home:
My AP is connected to it's own NIC in my router box (running linux). The DHCP server on the box will give people coming over that interface non-routable IPs, and iptables is configured to drop everything not going to the router from that interface. If a user attempts to go to a web page iptables routes the traffic to the routers web server which tells them how to set up a VPN, if they have a username/pass (my gf is always messing it up, so she needs instructions :) ). Once VPNing to the router you're given an IP on the normal wired network and off to the races. This way you get none of the downsides of WEP (insecure, slowdown, known key, etc) and all the benefits of encryption.
It sounds complicated, but really it's not. I can't see why more people aren't doing this as opposed to WEP. It's my understanding WEP==BAD.

Re:Crypto subsystems are notoriously difficult... (1)

thogard (43403) | more than 9 years ago | (#8825081)

Who are you going to trust? In '95 I wondered into a student dorm in Wash DC to buy a pixel machine. The price of the device went up by the time I got there and I wondered off to the ATM and when I got back the box had a "better offer" and disappeared. It had 82 CPUs that could deal with 40 des real quick. When it comes to cryptologist they come in 3 flavors, 1) the gov't versions, 2) civilian grade and 3) amature. From what what I've seen type 2==type 3. Take a look at how Schneier describes him self if you can find a 1st edition vs the later ones.

Re:Crypto subsystems are notoriously difficult... (4, Insightful)

kbonin (58917) | more than 9 years ago | (#8825466)

When I quit Cisco, I was the only real security programmer left in my business unit - all the other positions had been "outsourced" to Bangalore. That team didn't write "bad" code, it just wasn't robust. And they didn't get it. And management didn't care. And marketing just wants it to ship with the feature checklist complete.

I said it below, I'll say it again here. Companies have to CARE enough about security to have experienced crypto people do this sort of work. To design it, to implement it, and to test it.

But now its all about keeping things cheap.

No, the MS of hw is already here: (1)

carabela (688886) | more than 9 years ago | (#8824886)

Microsoft Hardware Worldwide [microsoft.com] .

And yes, they've got wireless routers running you-know-what!

AMERICAN GAYBOYS!!! JOIN aPPLE COMPUTER CLUB!!! (-1, Troll)

Anonymous Coward | more than 9 years ago | (#8824782)

Are you gay? Are you American? Do you own aPPLE hardware?

JOIN THE aPPLE COMPUTER CLUB!! CLUB THEME SONG IS "YMCA" by the Village People!!

YOUNG MAN, there's a place you can go - join now!!

Re:AMERICAN GAYBOYS!!! JOIN aPPLE COMPUTER CLUB!!! (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#8824788)

I LOVE THAT SONG!!

Re:AMERICAN GAYBOYS!!! JOIN aPPLE COMPUTER CLUB!!! (0)

okayiaT ver.65535 (769828) | more than 9 years ago | (#8825579)

but... ... ...
I am Japanese... :o)

So I guess... (2)

ForestGrump (644805) | more than 9 years ago | (#8824786)

Wifi is once again unsecure.

-Grump

Re:So I guess... (-1, Offtopic)

Anonymous Coward | more than 9 years ago | (#8824795)

Do you rememeber The WIPO Troll? Do you live his legacy? Do you know the sacrafices he made? I sure hope you do, and may God have mercy on your soul.

Re:So I guess... (1)

ForestGrump (644805) | more than 9 years ago | (#8824827)

no, no, no.
and lastly, I'm an athiest.

That's why you pay top dollar for cisco... (-1, Redundant)

Anonymous Coward | more than 9 years ago | (#8824789)

so you can have a tool that you are paying for their "better" proprietary ways of doing things which lock you into using their way, when something like this happens you decide it's easier to work with the load of cisco crap you have rather than change it out.

dictionary attack? (5, Interesting)

Njovich (553857) | more than 9 years ago | (#8824796)

Sure, this is a well done cracking tool, but isn't "cracked" a bit sensationalistic considering it still requires brute forcing the password? The weakness remains the password here, hardly the authentication scheme... good luck dictionary attacking a good password!

Re:dictionary attack? (4, Funny)

Anonymous Coward | more than 9 years ago | (#8824873)

Yeah, let me tell you, a dictionary attack WILL break a cisco router in seconds, every time.

Of course, not just any dictionary will do: you need a dictionary with not only simple English words, but with long definitions and even off-beat, obsolete words.

Routers are quiet small in the scheme of things, and they really can't stand up to a quick beating by, let's say the Oxford English dictionary, especially if the router is opened up and the electronics are exposed. No, those little dictionaries you get with a subscription to Time magazine won't do (after all, Time's vocabulary is pretty light-weight to begin with).

However, a quality rack-mounted cisco router will likely be protected in a secure data center or other secure closet. in that case, you'll have to take all the words in the dictionary and hash them up. And if the users aren't dumb, they'll pick tough passwords. It can take many years (or even decades) to successfully attack quality passwords.

I think the physical dictionary attack is the easier approach. Unless you permit your users to choose stupid passwords (like mine: "17Trees")

Re:dictionary attack? (1, Funny)

Anonymous Coward | more than 9 years ago | (#8825380)

Unless you permit your users to choose stupid passwords (like mine: "17Trees")
d00d, ur box is r00t3d. I'm in 127.0.0.1 n0w. Start crying, time to rm -fR /.

Re:dictionary attack? (4, Insightful)

MBAFK (769131) | more than 9 years ago | (#8824877)

"good luck dictionary attacking a good password"

The time to brute force the password is a combination of many factors not just the strength (length and composition) of the password. The amount of resources avaible to compute the hashes and the complexity of the algorithm used to create the hashes have a large effect on how long it will take to compute a match.

In this age it is becoming possible to precompute the hashes and then look them up, in that case the "strength" of the password becomes less important.

Re:precomputed hashes (0)

Anonymous Coward | more than 9 years ago | (#8825048)

Now there's something I never thought of - bajillions of possible passwords, what with mixing of case, numbers, and a few special characters across an unknown number of characters...

Why not sit down ONCE, and create your own dictionary of all possible passwords - which would be a huge job, but afterwards you could just do a simple lookup on the hash and your database would return the unencrypted password.

Considering an OS like Windows can last almost a decade before most people are upgraded to the next version, it might be worth spending a couple of years building such a dictionary to have as a resource.

Now, I eagerly await all those who wish to respond with either A) It's long since been done or, B) It's not practical yet due to the required processing & storage. In my ignorance, I don't know which is the case.

Re:dictionary attack? (1)

rmdyer (267137) | more than 9 years ago | (#8825464)

Aren't you assuming that the relationship between the number of bits in the password and the number of bits in the hash are not one to one?

If the number of bits possible in the password are 256, 512, or 1024, then password strength definitely does matter.

+2

salts? (1)

Heisenbug (122836) | more than 9 years ago | (#8825522)

"In this age it is becoming possible to precompute the hashes and then look them up, in that case the "strength" of the password becomes less important."

I would love to know how this works -- I thought it was pretty much useless. First because the storable keyspace is so much tinier than the total keyspace, and second because of salts.

IANACrypto person, but the basic idea with salts is that the router would say 'please send me your password hashed with the string "abcdefg".' The client then says, "oh, of course, that's hash('passwordsexgodabcdefg')". The evil sniffer has hash('passwordsexgod') stored in their lookup table, but that's totally useless in discovering what the client used. Since 'abcdefg' is a different string in each transaction, the lookup table becomes irrelevant.

I wasn't being sarcastic above -- I would love to know if this technique has somehow been overcome.

Re:dictionary attack? (0)

Anonymous Coward | more than 9 years ago | (#8825007)

I think aironet access points will kick you off the ap after 3 failed authentication attempts and will not let you associate for a minute or two. It seems like it would take a really long time to break a password if you only get 3 trys per minute.

Cool. Now there's a laugh (4, Interesting)

Moderation abuser (184013) | more than 9 years ago | (#8824798)

Cos the very very large corporation which I very recently used to work for has just rolled out Cisco based wireless across *all* of it's sites worldwide.

Re:Cool. Now there's a laugh (1)

BlackHorse (671909) | more than 9 years ago | (#8824850)

I think I know where you used to work, unless the company I used to work for did the same thing =P

Re:Cool. Now there's a laugh (3, Funny)

AKnightCowboy (608632) | more than 9 years ago | (#8825335)

I think I know where you used to work, unless the company I used to work for did the same thing =P

Woh, imagine that! Two different companies using wireless products from Cisco. What are the odds of that!?

Re:Cool. Now there's a laugh (2, Funny)

BlackHorse (671909) | more than 9 years ago | (#8825414)

I meant a "major" company "just" rolling out Cisco wireless to "all" locations.

Cisco WLAN AP != LEAP in all cases (3, Informative)

supton (90168) | more than 9 years ago | (#8824982)

EAP-TLS, EAP-TTLS, and other EAP/802.1x authentication mechanisms are also supported by Aironet 1100 and 1200 series APs. These use strong certificate-based authentication, which isn't practially vulnerable to dictionary attack. This, of course, requires you run a certicifate authority for your network, and means more work - but most companies running a VPN will already be doing this, and those that are not will do this to avoid having to put APs outside the firewall and maintain a VPN infrastructure for WLANs.

Yeah but, don't worry. (5, Funny)

FreeLinux (555387) | more than 9 years ago | (#8824799)

Because if you are using a Cisco network it is self-defending, self-securing and self-healing. No, really. I saw it on TV.

They had this little girl on the computer and she like, downloaded a worm. But, the network saw it and popped up a message on her screan that the worm was there. Then it said that it was like, isolating the worm and everything. Then it like, popped up another message that said the worm had been destroyed. It was like, way cool and I didn't even know that Cisco like, made antivirus software.

Of course the above is a joke but, what is not funny is that the television advertisement is well done and likely to be very influential to the typical PHB who will buy it hook, line and sinker.

Re:Yeah but, don't worry. (4, Funny)

drinkypoo (153816) | more than 9 years ago | (#8824860)

And like, the router was like BEEP BEEP BEEP BEEP and then it crashed, it was a really good config too.

Re:Yeah but, don't worry. (3, Informative)

slash-tard (689130) | more than 9 years ago | (#8824909)

Well Cisco does have some of the best HA hardware available. I think that qualifies for self healing. They also have 4 hour turn around on hardware repairs if you want to pay for it.

Cisco also has IDS software that will detect intrusions and update access lists on the appropriate routers on the fly. I think that qualifies for self securing and defending.

Re:Yeah but, don't worry. (1, Funny)

Anonymous Coward | more than 9 years ago | (#8824916)

They should have used Ti-Kwan-Leep authentication.

Hey Cisco, Boot to the Head! [beagleweb.com]

Re:Yeah but, don't worry. (3, Informative)

porkus (16839) | more than 9 years ago | (#8824994)

What this commercial is really about is the Cisco Security Agent [cisco.com] they are selling now. Comes preinstalled on some of their products, like the AVVID CallManager. It hooks into the system libraries and watches call sequences for potential virus/worm/trojan-related activity and stops the application from running if it detects something that fits the profile.

Attention Slashbot Bitches: (-1, Troll)

Anonymous Coward | more than 9 years ago | (#8824803)

...MY ANUS IS BLEEDING!

Happy birthday to me.
Happy birthday to me.
I paid for some pussy,
but you got some for free.

Eat snackysmores.

Re:Attention Slashbot Bitches: (0)

Anonymous Coward | more than 9 years ago | (#8825739)

> Happy birthday to me.
> Happy birthday to me.
> I paid for some pussy,
> but you got some for free.

u-mmmm.

That song is like a
"DENKI GROOVE - Happy Birthday.mp3"
Japanese music.
I think.
Dig.
o.

_
by okayiaT ver.65535 [slashdot.org]
# CheapGbE!GbE!!TheKLF!KLF!!TheRMS!RMS!! And a meme sparks...

Another news source (0)

Anonymous Coward | more than 9 years ago | (#8824804)

A more detailed source [spacker.net] .

I don't feel safe... (5, Funny)

cdavies (769941) | more than 9 years ago | (#8824851)

.. with my Open System Wireless, with MAC address access control, but at least my intruders will be using a better class of operating system, on which you can easily spoof MACs.

Script kiddies using canned cracks on me from Windows machines would just make me feel dirty.

This has been in the wild for months (4, Informative)

codepunk (167897) | more than 9 years ago | (#8824854)

I seen the leap cracker downloadable for at least several months now. This means it has been in use for quite some time no sense in worrying about it now.

So freakin what???? (-1, Troll)

Anonymous Coward | more than 9 years ago | (#8824865)

This is Slashdot buddy. Nobody here would ever fork out the dough to by a real Cisco product anyway so this will make no difference to any Slashdotter except for the very few that might like to utilize the exploit.

The closest any Slashdotter will come to buying a Cisco product is LinkSys. Now, even though Cisco now owns LinkSys, I don't think that anyone would go so far as to call a LinkSys router a Cisco product and LinkSys routers do not support LEAP anyway.

Not quite a crack (5, Interesting)

russotto (537200) | more than 9 years ago | (#8824866)

This is an offline dictionary attack, not a cryptographic break as has been done to WEP. If you use a strong password (one not in the dictionary), this won't break it. I don't know if preventing offline attacks was a goal of LEAP; if it was, it's fair to describe this as a crack, but if not, this is really just a tool to automate what was already known to be possible.

Re:Not quite a crack (2, Informative)

wasabii (693236) | more than 9 years ago | (#8825533)

Read the article. They use a weakness in the establishment of the connection to DRAMATICALLY reduce the time it takes for a dictionary attack, by gaining knowledge of the last two bytes of the NT hash.

Not really an issue for large businesses... (5, Interesting)

stienman (51024) | more than 9 years ago | (#8824920)

Since large businesses use secure VPN over any insecure channel (wireless, internet, dialup, even inside their own wired network) then it will only affect small businesses or those with poor security specialists who try to save money by putting the security into the network infrastructure.

Unfortunately while the firmware may be upgradeable, the cryptographic functions are usually implemented in hardware (better performance) and it may be hard, if not impossible, to secure the authentication so this kind of attack is harder.

What they really should do is have a public/private key for each access point, with the SSID set to the public key. Then any client can transmit to the access point without possibility of eavesdropping. This would be used to set up the secure LEAP session. Since the password is never sent back to the client then it's not going to be breakable by offline brute force attacks.

Of course, in the end anything is breakable given enough time and/or money.

-Adam

Offline attack (5, Interesting)

Knightmare (12112) | more than 9 years ago | (#8824931)

Many people here are talking about the length of time it takes to brute the password. I saw a demonstration of the asleap tool about 1/2 a year ago and it took 15 seconds to reveal the password. Something you need to keep in mind is the fact that there is no salt involved in the password hash for LEAP. So a precached hash of the possible passwords is very easy. All you need is lots of disk space and a well written index of the hashes.

There are quite a few others that are saying well thats only if you let your users pick bad passwords... Come on guys, have you actually worked in the real world? Normal users can't remember crazy passwords, they are going to pick their dog and their favorite football player's number put together. Or their aniversary and the current food they are eating.

Keeping a dictionary of enough passwords to get into the network would be trivial. All you need is one user with a weak password to get in, after that who cares how strong the rest are.

Re:Offline attack (2, Interesting)

Anime_Fan (636798) | more than 9 years ago | (#8825482)

Come on guys, have you actually worked in the real world? Normal users can't remember crazy passwords, they are going to pick their dog and their favorite football player's number put together. Or their aniversary and the current food they are eating.

At least we force hard passwords for administrators.
I've got some 7 complex passwords for admin accounts at work.
Add 2 for my regular accounts there.
Add 1 for Lotus Notes there.
Add 1 for my user at my home server.
Add 1 for root at the server.
Add 5 for the encrypted partitions on the server (one of which is 20 characters long).
Add 2 for my laptop.
Add 1 for my university logon.

It's easy to remember passwords once you learn how to create _good_ ones (that aren't based on dogs name + 3-digit number that you raise by 1 every 90 days).

But yes, most of my users tend to forget their passwords and need me to reset them once a month.
And the rest of the bunch use as weak passwords as they can.

The good thing is, their accounts don't matter to me. It's only some files they're going to find.
The admin accounts, OTOH can access any users' files in an instant (saved locally on the computer or on Novell doesn't matter). This is the account that needs protection.
That, and keeping the company off the internet, wireless networks et al.

Does the US government want insecure WiFi? (4, Interesting)

throwaway18 (521472) | more than 9 years ago | (#8824939)

A conspiracy theory.

WEP is broken by design. A few engineers who don't know anything about cryptanalysis making their own encryption system that turns out to be broken is quite plausable however wifi standards are set by the IEEE. The IEEE is not stupid.

Was WEP deliberatly broken to make government snooping easier?
That may seem ludicrus now but what if the likes of consume [consume.net] suceed in their goal of building mesh networks across citys? Securing wireless connections at VPN or application level is so much hassle that only 0.01% of users bother.

The reaction of the American government to the new Chinese wifi encryption standard lends weight to this theory. Supporting WAPI just means hardware manufacturers have to write a bit more software. Once it's in the software it will no doubt be supplied as standard worldwide. It may actuall be secure with little work. Why else would the American government threaten retailation over somthing so obscure?

Re:Does the US government want insecure WiFi? (1, Interesting)

Anonymous Coward | more than 9 years ago | (#8825016)

"The reaction of the American government to the new Chinese wifi encryption standard lends weight to this theory. Supporting WAPI just means hardware manufacturers have to write a bit more software. Once it's in the software it will no doubt be supplied as standard worldwide. It may actuall be secure with little work. Why else would the American government threaten retailation over somthing so obscure?"

easy because of the other side of it....

"China's WLAN standard has provoked concern among U.S. companies and industry groups for fear that it could fracture the market for WLAN equipment. Also creating some apprehension is a requirement that foreign WLAN equipment vendors must license the technology through coproduction agreements with Chinese companies. The U.S. Information Technology Office (USITO), a U.S. industry group, has said this provision unfairly requires U.S. companies to share proprietary technology with Chinese companies that may also be competitors. "

So there in a nutshell are the other reasons why WAPI is not being embraced by the US government or US businesses. On the other hand I like your tinfoil hat angle because it is so shiny ;-)

Re:Does the US government want insecure WiFi? (2, Informative)

eggboard (315140) | more than 9 years ago | (#8825038)

WEP was weak (not broken) by design: when the spec was being designed, the US government still had its onerous cryptographic export restrictions (classifying them as munitions) and one person involved in setting the WEP spec said they erred towards weakness in part because of that climate, and in part because they didn't have computational juice available. The broken parts are just broken, but the strength was intentional.

On the Chinese front, you're way off base. The problem is that the Chinese government requires that foreign companies provide their intellectual property (chip designs, etc.) to one of a dozen Chinese firms that are licensed to create WAPI. So it's not a matter of just adding code to firmware, in which case it might be Yet Another Redundant Standard. Instead, the Chinese government is requiring that non-Chinese firms essentially give away their technological advances.

Re:Does the US government want insecure WiFi? (1)

tietokone-olmi (26595) | more than 9 years ago | (#8825280)

And besides, the RC4 weak key scheduling thing wasn't known until after the WEP specification became widely accepted.

Re:Does the US government want insecure WiFi? (1, Insightful)

Anonymous Coward | more than 9 years ago | (#8825454)

"The problem is that the Chinese government requires that foreign companies provide their intellectual property (chip designs, etc.) to one of a dozen Chinese firms that are licensed to create WAPI. So it's not a matter of just adding code to firmware, in which case it might be Yet Another Redundant Standard. Instead, the Chinese government is requiring that non-Chinese firms essentially give away their technological advances."

this is actually quite true. They want you to turn over your source code to one of 11 (now its 24 I think) 'certified' chinese companies, who would then design and decide whether WAPI goes into software or hardware and where. They then make the required changes. _this_ is the reason why Intel is so pissed about this, and Dick Cheney has been asked by many CEOs to bring this topic up on his visit to China.

With all the work that IEEE 802.11i has done getting AES-CCMP in, wireless security is now almost top-notch, there is no real need for another protocol unless the Chinese govt wants a protocol with backdoors so that they can spy on their citizens.

Re:Does the US government want insecure WiFi? (1)

AKnightCowboy (608632) | more than 9 years ago | (#8825450)

Securing wireless connections at VPN or application level is so much hassle that only 0.01% of users bother.

Ever hear of SSL? How difficult is it to open a browser and go to an SSL website? How difficult is it to use IMAPS or POPS? How difficult is it to use SSH instead of Telnet? Getting users to understand PKI and client side certificates to manage in their IPSEC VPN client is one thing (and I agree it's entirely too complex a solution for the problem people use it to solve), but teaching users to type https instead of http isn't that difficult. I blame most of bad press encryption has gotten over the past few years on IPSEC. It's a bloated solution that is unnecessarily complicated and must integrate tightly into the client's IP stack to handle the lower-layer levels of encryption.

Re:Does the US government want insecure WiFi? (1)

rmdyer (267137) | more than 9 years ago | (#8825572)

Related to this, since I've gotten into networking, oh 18 years or so ago, I've been told that it is illegal to develop your own encryption that can't be broken by the government. So you either don't use encryption, or you must use a publicly available encryption like WEP, SSL, etc.

What I want to know is, is this true? Would sending random looking data to some IP addresses get you into trouble?

-1

'twas on http://dis.hert.org a few days ago (4, Interesting)

acz (120227) | more than 9 years ago | (#8824948)

Slashdot's always a bit late on interesting security issues. This news [hert.org] was on the Hacker Emergency Response team beta new website [hert.org] a few days ago.


The site which accidently looks a lot like slashdot, focuses on quality security news; no vuln reports people don't care about... all the latest news and white papers.


A cool white paper on utf-8 shellcodes was released [hert.org] on it too.

Re:'twas on http://dis.hert.org a few days ago (1)

qtp (461286) | more than 9 years ago | (#8825232)

The site which accidently looks a lot like slashdot,

Are you sure that incedentally wouldn't be a better term? Lots of developers start with slashcode when building their forums, and they are not ashamed of the fact (nor should they be.

It only makes sense to use something that works well and is already written if it asddresses your needs and is offered freely by its creators.

no vuln reports people don't care about...

It's nice to know that their knowledge is so complete that they can make that decision for their readers. Even (especially?) obscur vulns and seemingly insignificant theoretical flaws have a tendency to blow up later if they are not addressed in a reasonable time. What makes the vuln appear insignificant is often the failure of anyone (developers, security specialists, and crackers) to understand the ramifications when it is first announced. Just because no-one has posted a "proof of concept" at the moment does not mean that it cannot be exploited or is not already being exploited by someone who is more quiet with their knowledge.

all the latest news and white papers.

The papers are the meat of the subject, if they are well written and thoroughly considered. It's good to someone attempting to provide a central library for the community to access.

It looks like a great site, and I'm sure it'll be quite useful. It would be nice if their readers would step forward and contribute a bit more (most stories on the front page have zero comments), as all security papers and news can use a bit of community criticism to test their theses. It will be interesting to see if the timeliness of their reports can continue to be as good as it is once they start getting the volume of participation that you see here.

Thanks for the link.

"Cracked"? (2, Insightful)

Anonymous Coward | more than 9 years ago | (#8824996)

Whee! /. goes security journalism:

Dictionary attack == LEAP is cracked!

Need to move to PEAP ASAP (3, Interesting)

hta (7593) | more than 9 years ago | (#8825008)

So NOW I know why everyone's telling me that LEAP is not the end-game, and we need to move to systems based on PEAP (which is supposed to be an open standard, as opposed to LEAP which is proprietary) or some other, even newer variant.
Security protocols are like windows (the physical kind). Once they're broken, duct tape is not the answer.

Re:Need to move to PEAP ASAP (1)

Mordant (138460) | more than 9 years ago | (#8825707)

Show me a PEAP implementation for Linux, or Mac OS/X, if PEAP is so 'open'.

Offline Dictionary Attacks (1, Informative)

Anonymous Coward | more than 9 years ago | (#8825072)

Offline Dictionary Attacks do work on "strong" passwords. I got the hash of my Dad's strong Mac OS X password (something like "l;770gH>K") and cracked it using John the Ripper in about 45 days using an old Power Mac G4 400mhz machine. It's not hard, you just have to be patient. To be fair, I think OS X uses SHA1 as opposed to MD5 (which would have taken a lot longer to crack probably)

WPA-PSK at risk in similar circumstances (5, Informative)

eggboard (315140) | more than 9 years ago | (#8825083)

The LEAP problem is pretty egregious because PEAP and EAP-TTLS are in wide use -- both of which encrypt the authentication process protecting against just sucking down a transaction for offline analysis. PEAP was supposedly supported by Microsoft and Cisco, but I don't see how Cisco is supporting it by releasing EAP-FAST, which is an alternate approach that's not as strong as PEAP. (PEAP is also supported by Mac OS X 10.3, just by the way, as well as third parties who made 802.1X authentication software clients.)

But remember that this problem isn't limited to LEAP. As Robert Moskowitz of ICSA Labs wrote last November, poor WPA preshared key passphrase choice can allow WPA keys to be cracked [wifinetnews.com] . WPA (Wi-Fi Protected Access) is a fix to WEP that involves dramatically more complexity and sophistication in deriving per-packet keys.

However, if you choose a dictionary-crackable passphrase of under 20 characters in WPA, you hit the same problem as LEAP: a cracker can trigger a deauthentication, capture the reauthentication in less than a minute, and then crack at their leisure.

WPA-PSK will probably only be used in home and small office networks, where passphrases may be poorly chosen. I have spoken to manufacturers about changing the presentation layer: don't let users pick bad passwords. So far, to no avail. Not even a recommendation from the Wi-Fi Alliance.

how long for the offline crack? (0)

Matey-O (518004) | more than 9 years ago | (#8825127)

I always thought LEAP's strengths were in the time based key exchange. If the keys are exchanged some aribtrarily short period of time, you won't have the time to do a 128-bit crack.

Not having used LEAP, during a 'deauthentication' is there any notification to the client that the wireless subsystem is 're-authenticating'?

Allways on the ball (4, Informative)

RustyTaco (301580) | more than 9 years ago | (#8825309)

Wow, this is slow on the uptake even for slashdot. This was demonstrated last year at DefCon in August. It works because, as somebody else mentioned, there is no salt on the hash so you can pre-compute massive hash dictionaries. Also, it's a bastardized MS-CHAP which stupidly pads the hash with two constant characters so you can almost instantly cut down the keyspace you need to brute force by a huge margin.
The limiting factor is how fast your attack machine can read your pre-computed dictionaries off the disk.

- RustyTaco

Hire EXPERIENCED security people, not cheap ones! (4, Interesting)

kbonin (58917) | more than 9 years ago | (#8825363)

This is yet another example of why you need to hire security programmers with actual experience in the field, not just outsource it to a cheap Indian programming group with no real experience writing robust protocols.

I'm an ex Cisco security programmer, and thats exactally what was happening before I quit. I wish I could say more...

Sigh... (0)

Anonymous Coward | more than 9 years ago | (#8825616)

I feel for you man. But my teacher told me, and I stick to this in my life: "The cream will always rise."

Once again, securing the network isn't effective (1)

adamsc (985) | more than 9 years ago | (#8825556)

It's funny how much effort people put into solving the wrong problem - if you simply treat your wireless network like the Internet and secure your actual services, none of this is a concern.
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