libtar: Arbitraty code execution

Background

libtar is a C library for manipulating POSIX tar files.

Description

An integer overflow error within the “th_read()” function when processing long names or link extensions can be exploited to cause a heap-based buffer overflow via a specially crafted archive.

Impact

A remote attacker could entice a user to open a specially crafted file using a program linked against libtar, possibly resulting in execution of arbitrary code with the privileges of the process or a Denial of Service condition.

Workaround

There is no known workaround at this time.

Resolution

All libtar users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=dev-libs/libtar-1.2.20-r2"