Asterisk Project Security Advisory – AST-2014-017

Product Asterisk
Summary Permission escalation through ConfBridge
actions/dialplan functions
Nature of Advisory Permission Escalation
Susceptibility Remote Authenticated Sessions
Severity Minor
Exploits Known No
Reported On November 4, 2014
Reported By Gareth Palmer
Posted On 20 November, 2014
Last Updated On November 20, 2014
Advisory Contact Kevin Harwell
CVE Name Pending

Description The CONFBRIDGE dialplan function when executed from an
external protocol (for instance AMI), could result in a
privilege escalation. Also, the AMI action
“ConfbridgeStartRecord” could also be used to execute
arbitrary system commands without first checking for system
access.

Resolution Asterisk now inhibits the CONFBRIDGE function from being
executed from an external interface if the live_dangerously
option is set to no. Also, the “ConfbridgeStartRecord” AMI
action is now only allowed to execute under a user with
system level access.

Affected Versions
Product Release
Series
Asterisk Open Source 11.x All versions
Asterisk Open Source 12.x All versions
Asterisk Open Source 13.x All versions
Certified Asterisk 11.6 All versions

Corrected In
Product Release
Asterisk Open Source 11.14.1, 12.7.1, 13.0.1
Certified Asterisk 11.6-cert8

Patches
SVN URL Revision
http://downloads.asterisk.org/pub/security/AST-2014-017-11.diff Asterisk
11
http://downloads.asterisk.org/pub/security/AST-2014-017-12.diff Asterisk
12
http://downloads.asterisk.org/pub/security/AST-2014-017-13.diff Asterisk
13
http://downloads.asterisk.org/pub/security/AST-2014-017-11.6.diff Certified
Asterisk
11.6

Links https://issues.asterisk.org/jira/browse/ASTERISK-24490

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This document may be superseded by later versions; if so, the latest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-2014-017.pdf and
http://downloads.digium.com/pub/security/AST-2014-017.html

Revision History
Date Editor Revisions Made
November 18, 2014 Kevin Harwell Initial advisory created

Asterisk Project Security Advisory – AST-2014-017
Copyright (c) 2014 Digium, Inc. All Rights Reserved.
Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.