exploit the possibilities

Asterisk Project Security Advisory - AST-2011-013

Asterisk Project Security Advisory - AST-2011-013
Posted Dec 9, 2011
Authored by Terry Wilson | Site asterisk.org

Asterisk Project Security Advisory - It is possible to enumerate SIP usernames when the general and user/peer NAT settings differ in whether to respond to the port a request is sent from or the port listed for responses in the Via header. In 1.4 and 1.6.2, this would mean if one setting was nat=yes or nat=route and the other was either nat=no or nat=never. In 1.8 and 10, this would mean when one was nat=force_rport or nat=yes and the other was nat=no or nat=comedia.

tags | advisory
MD5 | def059b81354c49994d1128fdf133f47

Asterisk Project Security Advisory - AST-2011-013

Change Mirror Download
               Asterisk Project Security Advisory - AST-2011-013

Product Asterisk
Summary Possible remote enumeration of SIP endpoints with
differing NAT settings
Nature of Advisory Unauthorized data disclosure
Susceptibility Remote unauthenticated sessions
Severity Minor
Exploits Known Yes
Reported On 2011-07-18
Reported By Ben Williams
Posted On
Last Updated On December 7, 2011
Advisory Contact Terry Wilson <twilson@digium.com>
CVE Name

Description It is possible to enumerate SIP usernames when the general
and user/peer NAT settings differ in whether to respond to
the port a request is sent from or the port listed for
responses in the Via header. In 1.4 and 1.6.2, this would
mean if one setting was nat=yes or nat=route and the other
was either nat=no or nat=never. In 1.8 and 10, this would
mean when one was nat=force_rport or nat=yes and the other
was nat=no or nat=comedia.

Resolution Handling NAT for SIP over UDP requires the differing
behavior introduced by these options.

To lessen the frequency of unintended username disclosure,
the default NAT setting was changed to always respond to the
port from which we received the request-the most commonly
used option.

Warnings were added on startup to inform administrators of
the risks of having a SIP peer configured with a different
setting than that of the general setting. The documentation
now strongly suggests that peers are no longer configured
for NAT individually, but through the global setting in the
"general" context.

Affected Versions
Product Release Series
Asterisk Open Source All All versions

Corrected In
As this is more of an issue with SIP over UDP in general, there is no
fix supplied other than documentation on how to avoid the problem. The
default NAT setting has been changed to what we believe the most
commonly used setting for the respective version in Asterisk 1.4.43,
1.6.2.21, and 1.8.7.2.

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://downloads.digium.com/pub/security/AST-2011-013.pdf and
http://downloads.digium.com/pub/security/AST-2011-013.html

Revision History
Date Editor Revisions Made

Asterisk Project Security Advisory - AST-2011-013
Copyright (c) 2011 Digium, Inc. All Rights Reserved.
Permission is hereby granted to distribute and publish this advisory in its
original, unaltered form.

Comments

RSS Feed Subscribe to this comment feed

No comments yet, be the first!

Login or Register to post a comment

File Archive:

September 2019

  • Su
  • Mo
  • Tu
  • We
  • Th
  • Fr
  • Sa
  • 1
    Sep 1st
    1 Files
  • 2
    Sep 2nd
    38 Files
  • 3
    Sep 3rd
    30 Files
  • 4
    Sep 4th
    15 Files
  • 5
    Sep 5th
    12 Files
  • 6
    Sep 6th
    17 Files
  • 7
    Sep 7th
    3 Files
  • 8
    Sep 8th
    1 Files
  • 9
    Sep 9th
    24 Files
  • 10
    Sep 10th
    22 Files
  • 11
    Sep 11th
    22 Files
  • 12
    Sep 12th
    15 Files
  • 13
    Sep 13th
    5 Files
  • 14
    Sep 14th
    0 Files
  • 15
    Sep 15th
    0 Files
  • 16
    Sep 16th
    0 Files
  • 17
    Sep 17th
    0 Files
  • 18
    Sep 18th
    0 Files
  • 19
    Sep 19th
    0 Files
  • 20
    Sep 20th
    0 Files
  • 21
    Sep 21st
    0 Files
  • 22
    Sep 22nd
    0 Files
  • 23
    Sep 23rd
    0 Files
  • 24
    Sep 24th
    0 Files
  • 25
    Sep 25th
    0 Files
  • 26
    Sep 26th
    0 Files
  • 27
    Sep 27th
    0 Files
  • 28
    Sep 28th
    0 Files
  • 29
    Sep 29th
    0 Files
  • 30
    Sep 30th
    0 Files

Top Authors In Last 30 Days

File Tags

Systems

packet storm

© 2019 Packet Storm. All rights reserved.

Services
Security Services
Hosting By
Rokasec
close