[Full-disclosure] AST-2012-007: Remote crash vulnerability in IAX2 channel driver.

Asterisk Project Security Advisory - AST-2012-007

Product Asterisk
Summary Remote crash vulnerability in IAX2 channel driver.
Nature of Advisory Remote crash
Susceptibility Established calls
Severity Moderate
Exploits Known No
Reported On March 21, 2012
Reported By mgrobecker
Posted On May 29, 2012
Last Updated On May 29, 2012
Advisory Contact Richard Mudgett < rmudgett AT digium DOT com >
CVE Name CVE-2012-2947

Description A remotely exploitable crash vulnerability exists in the
IAX2 channel driver if an established call is placed on
hold without a suggested music class. For this to occur,
the following must take place:

1. The setting mohinterpret=passthrough must be set on the
end placing the call on hold.

2. A call must be established.

3. The call is placed on hold without a suggested
music-on-hold class name.

When these conditions are true, Asterisk will attempt to
use an invalid pointer to a music-on-hold class name. Use
of the invalid pointer will either cause a crash or the
music-on-hold class name will be garbage.

Resolution Asterisk now sets the extra data parameter to null if the
received control frame does not have any extra data.

Affected Versions
Product Release Series
Certified Asterisk 1.8.11-cert All versions
Asterisk Open Source 1.8.x All versions
Asterisk Open Source 10.x All versions

Corrected In
Product Release
Certified Asterisk 1.8.11-cert2
Asterisk Open Source, 10.4.1

SVN URL Revision
http://downloads.asterisk.org/pub/security/AST-2012-007-1.8.11-cert.diff v1.8.11-cert
http://downloads.asterisk.org/pub/security/AST-2012-007-1.8.diff v1.8
http://downloads.asterisk.org/pub/security/AST-2012-007-10.diff v10

Links https://issues.asterisk.org/jira/browse/ASTERISK-19597

Asterisk Project Security Advisories are posted at

This document may be superseded by later versions; if so, the latest
version will be posted at
http://downloads.digium.com/pub/security/AST-2012-007.pdf and

Revision History
Date Editor Revisions Made
05/29/2012 Richard Mudgett Initial release.

Asterisk Project Security Advisory - AST-2012-007
Copyright (c) 2012 Digium, Inc. All Rights Reserved.
Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.

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