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

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

Affected Packages

app-shells/mksh on all architectures
Affected versions < 50c
Unaffected versions >= 50c

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.

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

Release Date
November 02, 2015

Latest Revision
November 02, 2015: 2

Severity
normal

Exploitable
local

Bugzilla entries