GNU C Library: Integer overflow
Gentoo Linux Security Advisory
||GLSA 200707-04 / glibc
||July 03, 2007
||July 03, 2007: 01
An integer overflow in the dynamic loader, ld.so, could result in the
execution of arbitrary code with escalated privileges.
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
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.
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.
There is no known workaround at this time.
All users should upgrade to the latest version:
Code Listing 3.1: Resolution
# emerge --sync
# emerge --ask --oneshot --verbose ">=sys-libs/glibc-2.5-r4"