Asterisk Security Team
2011-Feb-21 21:45 UTC
[asterisk-announce] AST-2011-002: Multiple array overflow and crash vulnerabilities in UDPTL code
Asterisk Project Security Advisory - AST-2011-002
Product Asterisk
Summary Multiple array overflow and crash vulnerabilities in
UDPTL code
Nature of Advisory Exploitable Stack and Heap Array Overflows
Susceptibility Remote Unauthenticated Sessions
Severity Critical
Exploits Known No
Reported On January 27, 2011
Reported By Matthew Nicholson
Posted On February 21, 2011
Last Updated On February 21, 2011
Advisory Contact Matthew Nicholson <mnicholson at digium.com>
CVE Name
Description When decoding UDPTL packets, multiple stack and heap based
arrays can be made to overflow by specially crafted packets.
Systems doing T.38 pass through or termination are vulnerable.
Resolution The UDPTL decoding routines have been modified to respect the
limits of exploitable arrays.
In asterisk versions not containing the fix for this issue,
disabling T.38 support will prevent this vulnerability from
being exploited. T.38 support can be disabled in chan_sip by
setting the t38pt_udptl option to "no" (it is off by
default).
t38pt_udptl = no
The chan_ooh323 module should also be disabled by adding the
following line in modles.conf.
noload => chan_ooh323
Affected Versions
Product Release Series
Asterisk Open Source 1.4.x All versions
Asterisk Open Source 1.6.x All versions
Asterisk Business Edition C.x.x All versions
AsteriskNOW 1.5 All versions
s800i (Asterisk Appliance) 1.2.x All versions
Corrected In
Product Release
Asterisk Open Source 1.4.39.2, 1.6.1.22, 1.6.2.16.2, 1.8.2.4
Asterisk Business Edition C.3.6.3
Patches
URL Branch
http://downloads.asterisk.org/pub/security/AST-2011-002-1.4.diff 1.4
http://downloads.asterisk.org/pub/security/AST-2011-002-1.6.1.diff 1.6.1
http://downloads.asterisk.org/pub/security/AST-2011-002-1.6.2.diff 1.6.2
http://downloads.asterisk.org/pub/security/AST-2011-002-1.8.diff 1.8
Links
Asterisk Project Security Advisories are posted at
http://www.asterisk.org/security
This document may be superseded by later versions; if so, the latest
version will be posted at
http://downloads.digium.com/pub/security/AST-2011-002.pdf and
http://downloads.digium.com/pub/security/AST-2011-002.html
Revision History
Date Editor Revisions Made
02/21/11 Matthew Nicholson Initial Release
Asterisk Project Security Advisory - AST-2011-002
Copyright (c) 2011 Digium, Inc. All Rights Reserved.
Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.