[VOIPSEC] AST-2017-010: Buffer overflow in CDR's set user

[Asterisk Security Team]

Asterisk Project Security Advisory - AST-2017-010

Product Asterisk
Summary Buffer overflow in CDR's set user
Nature of Advisory Buffer Overflow
Susceptibility Remote Authenticated Sessions
Severity Moderate
Exploits Known No
Reported On October 9, 2017
Reported By Richard Mudgett
Posted On
Last Updated On October 25, 2017
Advisory Contact Rmudgett AT digium DOT com
CVE Name

Description No size checking is done when setting the user field for
Party B on a CDR. Thus, it is possible for someone to use
an arbitrarily large string and write past the end of the
user field storage buffer. The earlier AST-2017-001
advisory for the CDR user field overflow was for the Party
A buffer.

This currently affects any system using CDR's that also
make use of the following:

* The 'X-ClientCode' header within a SIP INFO message when
using chan_sip and

the 'useclientcode' option is enabled (note, it's disabled
by default).

* The CDR dialplan function executed from AMI when setting
the user field.

* The AMI Monitor action when using a long file name/path.

Resolution The CDR engine now only copies up to the maximum allowed
characters into the user field. Any characters outside the
maximum are truncated.

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 13.13 All Releases

Corrected In
Product Release
Asterisk Open Source 13.18.1, 14.7.1, 15.1.1
Certified Asterisk 13.13-cert7

Patches
SVN URL Revision
http://downloads.asterisk.org/pub/security/AST-2017-010-13.diff Asterisk
13
http://downloads.asterisk.org/pub/security/AST-2017-010-14.diff Asterisk
14
http://downloads.asterisk.org/pub/security/AST-2017-010-15.diff Asterisk
15
http://downloads.asterisk.org/pub/security/AST-2017-010-13.13.diff Certified
Asterisk
13.13

Links https://issues.asterisk.org/jira/browse/ASTERISK-27337

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This document may be superseded by later versions; if so, the latest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-2017-010.pdf and
http://downloads.digium.com/pub/security/AST-2017-010.html

Revision History
Date Editor Revisions Made
October 12, 2017 Richard Mudgett Initial Revision

Asterisk Project Security Advisory - AST-2017-010
Copyright © 2017 Digium, Inc. All Rights Reserved.
Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.