Lucene search

K
securityvulnsSecurityvulnsSECURITYVULNS:DOC:21116
HistoryJan 09, 2009 - 12:00 a.m.

AST-2009-001: Information leak in IAX2 authentication

2009-01-0900:00:00
vulners.com
8

EPSS

0.009

Percentile

82.3%

           Asterisk Project Security Advisory - AST-2009-001

±-----------------------------------------------------------------------+
| Product | Asterisk |
|----------------------±------------------------------------------------|
| Summary | Information leak in IAX2 authentication |
|----------------------±------------------------------------------------|
| Nature of Advisory | Unauthorized data disclosure |
|----------------------±------------------------------------------------|
| Susceptibility | Remote Unauthenticated Sessions |
|----------------------±------------------------------------------------|
| Severity | Minor |
|----------------------±------------------------------------------------|
| Exploits Known | Yes |
|----------------------±------------------------------------------------|
| Reported On | October 15, 2008 |
|----------------------±------------------------------------------------|
| Reported By | http://www.unprotectedhex.com |
|----------------------±------------------------------------------------|
| Posted On | January 7, 2009 |
|----------------------±------------------------------------------------|
| Last Updated On | January 7, 2009 |
|----------------------±------------------------------------------------|
| Advisory Contact | Tilghman Lesher < tlesher AT digium DOT com > |
|----------------------±------------------------------------------------|
| CVE Name | CVE-2009-0041 |
±-----------------------------------------------------------------------+

±-----------------------------------------------------------------------+
| Description | IAX2 provides a different response during authentication |
| | when a user does not exist, as compared to when the |
| | password is merely wrong. This allows an attacker to |
| | scan a host to find specific users on which to |
| | concentrate password cracking attempts. |
| | |
| | The workaround involves sending back responses that are |
| | valid for that particular site. For example, if it were |
| | known that a site only uses RSA authentication, then |
| | sending back an MD5 authentication request would |
| | similarly identify the user as not existing. The |
| | opposite is also true. So the solution is always to send |
| | back an authentication response that corresponds to a |
| | known frequency with which real authentication responses |
| | are returned, when the user does not exist. This makes |
| | it very difficult for an attacker to guess whether a |
| | user exists or not, based upon this particular |
| | mechanism. |
±-----------------------------------------------------------------------+

±-----------------------------------------------------------------------+
| Resolution | Upgrade to revision 167259 of the 1.2 branch or 167260 of |
| | the 1.4 branch or one of the releases noted below. |
±-----------------------------------------------------------------------+

±-----------------------------------------------------------------------+

Affected Versions
Product
----------------------------±--------±--------------------------------
Asterisk Open Source
----------------------------±--------±--------------------------------
Asterisk Open Source
----------------------------±--------±--------------------------------
Asterisk Open Source
----------------------------±--------±--------------------------------
Asterisk Addons
----------------------------±--------±--------------------------------
Asterisk Addons
----------------------------±--------±--------------------------------
Asterisk Addons
----------------------------±--------±--------------------------------
Asterisk Business Edition
----------------------------±--------±--------------------------------
Asterisk Business Edition
----------------------------±--------±--------------------------------
Asterisk Business Edition
----------------------------±--------±--------------------------------
Asterisk Business Edition
----------------------------±--------±--------------------------------
AsteriskNOW
----------------------------±--------±--------------------------------
s800i (Asterisk Appliance)
±-----------------------------------------------------------------------+

±-----------------------------------------------------------------------+

Corrected In
Product
--------------------------------------------±--------------------------
Asterisk Open Source
--------------------------------------------±--------------------------
Asterisk Open Source
--------------------------------------------±--------------------------
Asterisk Open Source
--------------------------------------------±--------------------------
Asterisk Business Edition
--------------------------------------------±--------------------------
Asterisk Business Edition
--------------------------------------------±--------------------------
Asterisk Business Edition
--------------------------------------------±--------------------------
s800i (Asterisk Appliance)
±-----------------------------------------------------------------------+

±-----------------------------------------------------------------------+

Patches
URL
-----------------------------------------------------------------±-----
http://downloads.digium.com/pub/security/AST-2009-001-1.2.diff
-----------------------------------------------------------------±-----
http://downloads.digium.com/pub/security/AST-2009-001-1.4.diff
-----------------------------------------------------------------±-----
http://downloads.digium.com/pub/security/AST-2009-001-1.6.0.diff
±-----------------------------------------------------------------------+

±-----------------------------------------------------------------------+
| Links | http://code.google.com/p/iaxscan/ |
±-----------------------------------------------------------------------+

±-----------------------------------------------------------------------+
| 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-2009-001.pdf and |
| http://downloads.digium.com/pub/security/AST-2009-001.html |
±-----------------------------------------------------------------------+

±-----------------------------------------------------------------------+

Revision History
Date
-----------------±-----------------------±----------------------------
2009-01-07
±-----------------------------------------------------------------------+
           Asterisk Project Security Advisory - AST-2009-001
          Copyright &#40;c&#41; 2009 Digium, Inc. All Rights Reserved.

Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.