libarchive (formerly named as bsdtar): Multiple PaX Extension Header Vulnerabilities

Background

libarchive is a library for manipulating different streaming archive formats, including certain tar variants, several cpio formats, and both BSD and GNU ar variants.

Description

CPNI, CERT-FI, Tim Kientzle, and Colin Percival reported a buffer overflow (CVE-2007-3641), an infinite loop (CVE-2007-3644), and a NULL pointer dereference (CVE-2007-3645) within the processing of archives having corrupted PaX extension headers.

Impact

An attacker can trick a user or automated system to process an archive with malformed PaX extension headers into execute arbitrary code, crash an application using the library, or cause a high CPU load.

Workaround

There is no known workaround at this time.

Resolution

All libarchive or bsdtar users should upgrade to the latest libarchive version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=app-arch/libarchive-2.2.4"