wiredmikey (1824622) writes "Security nightmares sparked by the Heartbleed OpenSSL vulnerability continue. According to Mandiant, now a unit of FireEye, an attacker was able to leverage the Heartbleed vulnerability against the VPN appliance of a customer and hijack multiple active user sessions. The attack bypassed both the organization's multifactor authentication and the VPN client software used to validate that systems connecting to the VPN were owned by the organization and running specific security software.
"Specifically, the attacker repeatedly sent malformed heartbeat requests to the HTTPS web server running on the VPN device, which was compiled with a vulnerable version of OpenSSL, to obtain active session tokens for currently authenticated users," Mandiant's Christopher Glyer explained. "With an active session token, the attacker successfully hijacked multiple active user sessions and convinced the VPN concentrator that he/she was legitimately authenticated."
After connecting to the VPN, the attacker attempted to move laterally and escalate his/her privileges within the victim organization, Mandiant said."