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

[GLSA]

Gentoo Linux Security Advisory

Title: chmlib, KchmViewer: Stack-based buffer overflow (GLSA 200511-23)
Severity: normal
Exploitable: remote
Date: November 28, 2005
Updated: May 28, 2009
Bug(s): #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: dev-libs/chmlib
Vulnerable: < 0.37.4
Unaffected: >= 0.37.4
Architectures: All supported architectures

Package: app-text/kchmviewer
Vulnerable: < 1.1
Unaffected: >= 1.1
Architectures: 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: