GNU C Library: Integer overflow — GLSA 200707-04

An integer overflow in the dynamic loader, ld.so, could result in the execution of arbitrary code with escalated privileges.

Affected Packages

sys-libs/glibc on the x86 architecture
Affected versions < 2.5-r4
Unaffected versions >= 2.5-r4

Background

The GNU C library is the standard C library used by Gentoo Linux systems. It provides programs with basic facilities and interfaces to system calls. ld.so is the dynamic linker which prepares dynamically linked programs for execution by resolving runtime dependencies and related functions.

Description

Tavis Ormandy of the Gentoo Linux Security Team discovered a flaw in the handling of the hardware capabilities mask by the dynamic loader. If a mask is specified with a high population count, an integer overflow could occur when allocating memory.

Impact

As the hardware capabilities mask is honored by the dynamic loader during the execution of suid and sgid programs, in theory this vulnerability could result in the execution of arbitrary code with root privileges. This update is provided as a precaution against currently unknown attack vectors.

Workaround

There is no known workaround at this time.

Resolution

All users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=sys-libs/glibc-2.5-r4"

References

Release Date
July 03, 2007

Latest Revision
July 03, 2007: 01

Severity
normal

Exploitable
local

Bugzilla entries