Linux users: are you at risk from kernel exploit?
More news about the recent break-ins on four Debian project servers emerged yesterday when Wichert Akkerman of the Debian project issued a new security alert about the situation. It appears that a flaw in the Linux kernel was exploited and a "sniffer" put in place to highjack passwords. It was with the purloined password that access to the Debian servers was achieved.
Akkerman explained in the security bulletin how the exploit was discovered:
Forensics revealed a burneye encrypted exploit. Robert van der Meulen managed to decrypt the binary which revealed a kernel exploit. Study of the exploit by the RedHat and SuSE kernel and security teams quickly revealed that the exploit used an integer overflow in the brk system call. Using this bug it is possible for a userland program to trick the kernel into giving access to the full kernel address space.
[ Read more ]