Arch Linux alert ASA-201606-13 (expat)

From:
    	     
 
Levente Polyak <anthraxx@archlinux.org> 
To:
    	     
 
arch-security@archlinux.org 
Subject:
    	     
 
[arch-security] [ASA-201606-13] expat: multiple issues 
Date:
    	     
 
Mon, 13 Jun 2016 01:50:29 +0200
Message-ID:
    	     
 
<46e98bc9-922f-05c2-3100-75e8f7b97be6@archlinux.org>
Arch Linux Security Advisory ASA-201606-13
==========================================

Severity: Medium
Date    : 2016-06-13
CVE-ID  : CVE-2012-6702 CVE-2016-5300
Package : expat
Type    : multiple issues
Remote  : Yes
Link    : https://wiki.archlinux.org/index.php/CVE

Summary
=======

The package expat before version 2.1.1-3 is vulnerable to multiple
issues including predictable random numbers and insufficient hash
entropy leading to denial of service.

Resolution
==========

Upgrade to 2.1.1-3.

# pacman -Syu "expat>=2.1.1-3"

The problems have been fixed upstream but no release is available yet.

Workaround
==========

None.

Description
===========

- CVE-2012-6702 (predictable random numbers)

It was found that when calling XML_Parse ahead of rand(), it causes the
pseudo random generator to generate non-random predictable numbers.

- CVE-2016-5300 (denial of service)

It was found that original fix for CVE-2012-0876 used too little
entropy for the hash initialization. This issue can be used to perform
a hash collision based denial of service attack.

Impact
======

A remote attacker is able to predict random numbers from the PRNG or
perform a hash based collision attack resulting in denial of service.

References
==========

https://access.redhat.com/security/cve/CVE-2012-6702
https://access.redhat.com/security/cve/CVE-2016-5300