GLSA 201511-01: MirBSD Korn Shell: Arbitrary code execution

http://security.gentoo.org/

Severity:	normal
Title:	MirBSD Korn Shell: Arbitrary code execution
Date:	11/02/2015
Bugs:	#524414
ID:	201511-01

Synopsis

An attacker who already had access to the environment could so append values to parameters passed through programs.

Background

MirBSD Korn Shell is an actively developed free implementation of the Korn Shell programming language and a successor to the Public Domain Korn Shell.

Affected packages

Package	Vulnerable	Unaffected	Architecture(s)
app-shells/mksh	< 50c	>= 50c	All supported architectures

Description

Improper sanitation of environment import allows for appending of values to passed parameters.

Impact

An attacker who already had access to the environment could so append values to parameters passed through programs (including sudo(8) or setuid) to shell scripts, including indirectly, after those programs intended to sanitise the environment, e.g. invalidating the last $PATH component.

Workaround

There is no known workaround at this time.

Resolution

All mksh users should upgrade to the latest version:

      # emerge --sync
      # emerge --ask --oneshot --verbose ">=app-shells/mksh-50c"

References

mksh R50c released, security fix

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-201511-01.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.