CERT-In Vulnerability Note CIVN-2009-46
Cisco IOS Software Session Initiation Protocol Denial of Service Vulnerability

Original Issue Date: April 09, 2009

Severity Rating: High

Systems Affected

•  Cisco IOS 12.0 through 12.4, when enabled for SIP

Overview

A vulnerability exists in the Session Initiation Protocol (SIP) implementation in Cisco IOS Software that can be exploited remotely to cause a denial of service condition.

Description

This vulnerability exists due to improper handling of Session Initiation Protocol (SIP) messages. An unauthenticated, remote attacker could exploit this vulnerability by sending a specially crafted SIP message to cause a reload. Repeated attempts could result in a persistent denial of service (DoS) condition.

Workarounds

•  Allow connection from legitimate device
•  Use anti spoofing methods in network

Solution

Apply appropriate fixed versions as mentioned in CISCO Security Advisory.
http://www.cisco.com/warp/public/707/cisco-sa-20090325-sip.shtml

Vendor Information

CISCO
http://www.cisco.com/warp/public/707/cisco-sa-20090325-sip.shtml

References

CISCO
http://www.cisco.com/warp/public/707/cisco-sa-20090325-sip.shtml
http://tools.cisco.com/security/center/viewAlert.x?alertId=17761

Security Focus
http://www.securityfocus.com/bid/34243

Secunia
http://secunia.com/advisories/34438

Security Tracker
http://securitytracker.com/id?1021902

CVE Name
CVE-2009-0636

Disclaimer

The information provided herein is on "as is" basis, without warranty of any kind.

Contact Information

Phone: +91-11-24368572

Postal address

Indian Computer Emergency Response Team (CERT-In)
Ministry of Communications and Information Technology
Electronics Niketan
6, C.G.O. Complex
New Delhi-110 003