Asterisk Project Security Advisory – AST-2018-002

Product Asterisk
Summary Crash when given an invalid SDP media format
description
Nature of Advisory Remote crash
Susceptibility Remote Authenticated Sessions
Severity Minor
Exploits Known No
Reported On January 15, 2018
Reported By Sandro Gauci
Posted On February 21, 2018
Last Updated On February 19, 2018
Advisory Contact Kevin Harwell
CVE Name

Description By crafting an SDP message with an invalid media format
description Asterisk crashes when using the pjsip channel
driver because pjproject’s sdp parsing algorithm fails to
catch the invalid media format description.

The severity of this vulnerability is lessened since an
endpoint must be authenticated prior to reaching the crash
point, or it’s configured with no authentication.

Resolution Stricter validation is now done when pjproject parses an
SDP’s media format description. Invalid values are now
properly handled.

Affected Versions
Product Release
Series
Asterisk Open Source 13.x All Releases
Asterisk Open Source 14.x All Releases
Asterisk Open Source 15.x All Releases
Certified Asterisk 13.18 All Releases

Corrected In
Product Release
Asterisk Open Source 13.19.2, 14.7.6, 15.2.2
Certified Asterisk 13.18-cert3

Patches
SVN URL Revision
http://downloads.asterisk.org/pub/security/AST-2018-002-13.diff Asterisk
13
http://downloads.asterisk.org/pub/security/AST-2018-002-14.diff Asterisk
14
http://downloads.asterisk.org/pub/security/AST-2018-002-15.diff Asterisk
15
http://downloads.asterisk.org/pub/security/AST-2018-002-13.18.diff Certified
Asterisk
13.18

Links https://issues.asterisk.org/jira/browse/ASTERISK-27582

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This document may be superseded by later versions; if so, the latest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-2018-002.pdf and
http://downloads.digium.com/pub/security/AST-2018-002.html

Revision History
Date Editor Revisions Made
January 30, 2018 Kevin Harwell Initial Revision

Asterisk Project Security Advisory – AST-2018-002
Copyright (c) 2018 Digium, Inc. All Rights Reserved.
Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.