GLSA 201611-19: Tar: Extract pathname bypass

http://security.gentoo.org/

Severity:	normal
Title:	Tar: Extract pathname bypass
Date:	11/22/2016
Bugs:	#598334
ID:	201611-19

Synopsis

A path traversal attack in Tar may lead to the remote execution of arbitrary code.

Background

The Tar program provides the ability to create and manipulate tar archives.

Affected packages

Package	Vulnerable	Unaffected	Architecture(s)
app-arch/tar	< 1.29-r1	>= 1.29-r1	All supported architectures

Description

Tar attempts to avoid path traversal attacks by removing offending parts of the element name at extract. This sanitizing leads to a vulnerability where the attacker can bypass the path name(s) specified on the command line.

Impact

The attacker can create a crafted tar archive that, if extracted by the victim, replaces files and directories the victim has access to in the target directory, regardless of the path name(s) specified on the command line.

Workaround

There is no known workaround at this time.

Resolution

All Tar users should upgrade to the latest version:

      # emerge --sync
      # emerge --ask --oneshot --verbose ">=app-arch/tar-1.29-r1"

References

CVE-2016-6321

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-201611-19.xml

Concerns?

Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org.