glibc: Insecure tempfile handling in catchsegv script

1. Gentoo Linux Security Advisory

Advisory Reference	GLSA 200410-19 / glibc
Release Date	October 21, 2004
Latest Revision	October 21, 2004: 01
Impact	normal
Exploitable	local

Package	Vulnerable versions	Unaffected versions	Architecture(s)
sys-libs/glibc	<= 2.3.4.20040808	revision >= 2.2.5-r9, revision >= 2.3.2-r12, revision >= 2.3.3.20040420-r2, revision >= 2.3.4.20040619-r2, >= 2.3.4.20040808-r1	All supported architectures

Related bugreports: #66358

Synopsis

The catchsegv script in the glibc package is vulnerable to symlink attacks, potentially allowing a local user to overwrite arbitrary files with the rights of the user running the script.

2. Impact Information

Background

glibc is a package that contains the GNU C library.

Description

The catchsegv script creates temporary files in world-writeable directories with predictable names.

Impact

A local attacker could create symbolic links in the temporary files directory, pointing to a valid file somewhere on the filesystem. When catchsegv script is called, this would result in the file being overwritten with the rights of the user running the utility, which could be the root user.

3. Resolution Information

Workaround

There is no known workaround at this time.

Resolution

All glibc users should upgrade to the latest version:

Code Listing 3.1: Resolution

# emerge sync
# emerge -pv sys-libs/glibc
# emerge sys-libs/glibc

4. References

CAN-2004-0968

Updated October 21, 2004

Summary: This is a Gentoo Linux Security Advisory

Security Team
Contact Address

Donate to support our development efforts.