search menu icon-carat-right cmu-wordmark

CERT Coordination Center

Integer overflow vulnerability in Asterisk driver for Cisco SCCP-enabled phones

Vulnerability Note VU#521252

Original Release Date: 2006-10-24 | Last Revised: 2007-01-19

Overview

Asterisk contains an integer overflow vulnerability. This vulnerability may allow an attacker to run arbitrary code.

Description

Asterisk is an open-source PBX software package that provides voicemail, three-way calling, and other features. Skinny Client Control Protocol (SCCP) is a proprietary Cisco protocol that is used to connect Cisco Call Managers and Cisco Voice over IP (VOIP) phones. Asterisk provides a driver for phones that use the SCCP protocol called chan_skinny.

An integer overflow vulnerability exists in the get_input(struct skinnysession *s) function which is found in the chan_skinny driver. Exploitation of this vulnerability may allow an attacker to execute arbitrary code.

Note that the chan_skinny driver only needs to be installed and loaded for a system to be vulnerable.

Impact

A remote, unauthenticated attacker may be able to execute arbitrary code with root privileges.

Solution

Update
The Asterisk Development Team has released an update to address this issue. See Asterisk update 1.2.13 and 1.0.12 for more details.


Restrict access
Restricting network access to port 2000/tcp on the Asterisk server may limit exposure to this vulnerability.

Do not load unnecessary drivers
Adding noload=>chan_skinny.so to the modules.conf file will prevent the vulnerable driver from loading at startup time.

Vendor Information

521252
 
Affected   Unknown   Unaffected

Asterisk

Updated:  October 24, 2006

Status

  Vulnerable

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

See http://www.asterisk.org/node/109 for more details.

If you have feedback, comments, or additional information about this vulnerability, please send us email.


CVSS Metrics

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A

References

Acknowledgements

This vulnerability report was based on information from Adam Boileau of Security-Assessment.com.

This document was written by Ryan Giobbi.

Other Information

CVE IDs: CVE-2006-5444
Severity Metric: 3.82
Date Public: 2006-10-18
Date First Published: 2006-10-24
Date Last Updated: 2007-01-19 17:44 UTC
Document Revision: 40

Sponsored by the Department of Homeland Security Office of Cybersecurity and Communications.