Debian Security Advisory DSA 453-1 (kernel)

The remote host is missing an update to kernel-source-2.2.20, kernel-image-2.2.20-i386, kernel-image-2.2.20-reiserfs-i386, kernel-image-2.2.20-amiga, kernel-image-2.2.20-atari, kernel-image-2.2.20-bvme6000, kernel-image-2.2.20-mac, kernel-image-2.2.20-mvme147, kernel-image-2.2.20-mvme16x, kernel-patch-2.2.20-powerpc announced via advisory DSA 453-1.

Paul Starzetz and Wojciech Purczynski of isec.pl discovered a critical security vulnerability in the memory management code of Linux inside the mremap(2) system call. Due to flushing the TLB (Translation Lookaside Buffer, an address cache) too early it is possible for an attacker to trigger a local root exploit. The attack vectors for 2.4.x and 2.2.x kernels are exclusive for the respective kernel series, though. We formerly believed that the exploitable vulnerability in 2.4.x does not exist in 2.2.x which is still true. However, it turned out that a second (sort of) vulnerability is indeed exploitable in 2.2.x, but not in 2.4.x, with a different exploit, of course. For the stable distribution (woody) this problem has been fixed in the following versions and architectures: kernel-source-2.2.20 source 2.2.20-5woody3 kernel-image-2.2.20-i386 i386 2.2.20-5woody5 kernel-image-2.2.20-reiserfs-i386 i386 2.2.20-4woody1 kernel-image-2.2.20-amiga m68k 2.20-4 kernel-image-2.2.20-atari m68k 2.2.20-3 kernel-image-2.2.20-bvme6000 m68k 2.2.20-3 kernel-image-2.2.20-mac m68k 2.2.20-3 kernel-image-2.2.20-mvme147 m68k 2.2.20-3 kernel-image-2.2.20-mvme16x m68k 2.2.20-3 kernel-patch-2.2.20-powerpc powerpc 2.2.20-3woody1 For the unstable distribution (sid) this problem will be fixed soon for the architectures that still ship a 2.2.x kernel package. We recommend that you upgrade your Linux kernel package.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%20453-1