GLSA 200511-23: chmlib, KchmViewer: Stack-based buffer overflow

http://security.gentoo.org/

Severity:	normal
Title:	chmlib, KchmViewer: Stack-based buffer overflow
Date:	11/28/2005
Bugs:	#110557
ID:	200511-23

Synopsis

chmlib and KchmViewer contain a buffer overflow vulnerability which may lead to the execution of arbitrary code.

Background

chmlib is a library for dealing with Microsoft ITSS and CHM format files. KchmViewer is a CHM viewer that includes its own copy of the chmlib library.

Affected packages

Package	Vulnerable	Unaffected	Architecture(s)
dev-libs/chmlib	< 0.37.4	>= 0.37.4	All supported architectures
app-text/kchmviewer	< 1.1	>= 1.1	All supported architectures

Description

Sven Tantau reported about a buffer overflow vulnerability in chmlib. The function "_chm_decompress_block()" does not properly perform boundary checking, resulting in a stack-based buffer overflow.

Impact

By convincing a user to open a specially crafted ITSS or CHM file, using KchmViewer or a program makes use of chmlib, a remote attacker could execute arbitrary code with the privileges of the user running the software.

Workaround

There is no known workaround at this time.

Resolution

All chmlib users should upgrade to the latest version:

    # emerge --sync
    # emerge --ask --oneshot --verbose ">=dev-libs/chmlib-0.37.4"

All KchmViewer users should upgrade to the latest version:


    # emerge --sync
    # emerge --ask --oneshot --verbose ">=app-text/kchmviewer-1.1"

References

CVE-2005-3318

Availability

This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200511-23.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.