Debian Security Advisory

DSA-1872-1 linux-2.6 -- denial of service/privilege escalation/information leak

Date Reported:
24 Aug 2009
Affected Packages:
Security database references:
In Mitre's CVE dictionary: CVE-2009-2698, CVE-2009-2846, CVE-2009-2847, CVE-2009-2848, CVE-2009-2849.
More information:

Several vulnerabilities have been discovered in the Linux kernel that may lead to denial of service, privilege escalation or a leak of sensitive memory. The Common Vulnerabilities and Exposures project identifies the following problems:

  • CVE-2009-2698

    Herbert Xu discovered an issue in the way UDP tracks corking status that could allow local users to cause a denial of service (system crash). Tavis Ormandy and Julien Tinnes discovered that this issue could also be used by local users to gain elevated privileges.

  • CVE-2009-2846

    Michael Buesch noticed a typing issue in the eisa-eeprom driver for the hppa architecture. Local users could exploit this issue to gain access to restricted memory.

  • CVE-2009-2847

    Ulrich Drepper noticed an issue in the do_sigalstack routine on 64-bit systems. This issue allows local users to gain access to potentially sensitive memory on the kernel stack.

  • CVE-2009-2848

    Eric Dumazet discovered an issue in the execve path, where the clear_child_tid variable was not being properly cleared. Local users could exploit this issue to cause a denial of service (memory corruption).

  • CVE-2009-2849

    Neil Brown discovered an issue in the sysfs interface to md devices. When md arrays are not active, local users can exploit this vulnerability to cause a denial of service (oops).

For the oldstable distribution (etch), this problem has been fixed in version 2.6.18.dfsg.1-24etch4.

We recommend that you upgrade your linux-2.6, fai-kernels, and user-mode-linux packages.

Note: Debian carefully tracks all known security issues across every linux kernel package in all releases under active security support. However, given the high frequency at which low-severity security issues are discovered in the kernel and the resource requirements of doing an update, updates for lower priority issues will normally not be released for all kernels at the same time. Rather, they will be released in a staggered or "leap-frog" fashion.

The following matrix lists additional source packages that were rebuilt for compatibility with or to take advantage of this update:

  Debian 4.0 (etch)
fai-kernels 1.17+etch.24etch4
user-mode-linux 2.6.18-1um-2etch.24etch4
Fixed in:

Debian GNU/Linux 4.0 (etch)

Architecture-independent component:
HP Precision:
Intel IA-32:
Intel IA-64:
Big-endian MIPS:
Little-endian MIPS:
IBM S/390:
Sun Sparc:

MD5 checksums of the listed files are available in the original advisory.