Full Disclosure mailing list archives
Re: ASN.1 telephony critical infrastructure warning - VOIP
From: Joseph M Hoffman <hoffjose () us ibm com>
Date: Thu, 19 Feb 2004 08:44:13 -0600
I agree that this is somewhat misleading in that VoIP and ASN1 do not go hand in hand. One item that maybe be an obvious is how to avoid the exploitation of VoIP no mater what protocol it is running is the use of a layered protective architecture. Many times I have seen enterprises run and "protect" every service under the sun but somehow miss building the VoIP server into that protective layering. The VoIP sever needs to only be contacted through a firewall,choke, and ids(ips) , set in a dmz, and treated just like any other component with policies, proceedures, msb's, and guidelines surronding it. The major root to the problems of new exploitations with the blended virus/worm attacks is not the individaul pieces of the enterprise but the overall security architecture is not looked at close enough. regards, Joseph M. Hoffman,CISSP, CCSA,CCSE,NSWC,SBFCC,B.A. I.B.M. Security & Privacy Services office 816-228-3275 mobile 816-721-3275 The highest reward for man's toil is not what he gets for it, but what he becomes by it. John Ruskin RJ Auburn <rj () voxeo com> To: Gadi Evron <ge () egotistical reprehensible net> cc: full-disclosure () lists netsys com, bugtraq () securityfocus com, Zak 02/17/2004 01:54 Dechovich <ZakGroups () secureol com> PM Subject: Re: ASN.1 telephony critical infrastructure warning - VOIP I would say that this is somewhat misleading. First of all not all VoIP services use ASN.1 encoding for the protocol. While H.323 does SIP does not. Additionally I suspect that not many of the carrier deployment of H.323 are using the MS ASN.1 libs as most of them are unix based (many of them will be running SPARC/Solaris). Now that being said if companies are allowing VoIP to the desktop for services like netmeeting there could be problems. RJ --- RJ Auburn CTO, Voxeo Corporation tel:+1-407-418-1800 On Feb 17, 2004, at 07:37, Gadi Evron wrote:
I apologize, but I am using these mailing lists to try and contact the different */CERT teams for different countries. As we all know, ASN.1 is a new very easy to exploit vulnerability. It attacks both the server and the end user (IIS and IE). We expect a new massive worm to come out exploiting this vulnerability in the next few days. Why should this all interest you beyond it being the next blaster? ASN is what VOIP is based on, and thus the critical infrastructure for telephony which is based on VOIP. This may be a false alarm, but you know how worms find their way into every network, private or public. It could (maybe) potentially bring the system down. I am raising the red flag, better safe than sorry. The two email messages below are from Zak Dechovich and myself on this subject, to TH-Research (The Trojan Horses Research Mailing List). The original red flag as you can see below, was raised by Zak. Skip to his message if you like. Gadi Evron. Subject: [TH-research] */CERT people: Critical Infrastructure and ASN.1 - VOIP [WAS: Re: [TH-research] OT: naming the fast approaching ASN.1 worm] Mail from Gadi Evron <ge () linuxbox org> All the */CERT people on the list: If you haven't read the post below, please do. Anyone checked into the critical infrastructure survivability of an ASN worm hitting? phone systems could possibly go down. We all know how worms find their way into any network, private or otherwise. and VOIP systems (which phone systems are based on nowadays) could go down. Heads-up! Finds them contingency plans.. :o) Any information would be appreciated, or if you need more information from us: +972-50-428610. Gadi Evron. Zak Dechovich wrote:Mail from Zak Dechovich <ZakGroups () SECUREOL COM> May I suggest the following: ASN1 is mainly used for the telephony infrastructure (VoIP), any code that attacks this infrastructure can be assigned with 'VoIP' prefix, followed by the attacked vendor (cisco, telrad, microsoft,etc.).for example, if (when) Microsoft's h323 stack will be attacked, thenameshould be VoIP.ms323.<variant>, or if Cisco's gatekeepers willcrash, letscall it VoIP.csgk.<variant> Your thoughts ? Zak Dechovich, Zak Dechovich, Managing Director SecureOL Ltd. Mobile: +972 (53) 828 656 Office: +972 (2) 675 1291 Fax: +972 (2) 675 1195- TH-Research, the Trojan Horses Research mailing list. List home page: http://ecompute.org/th-list
_______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.netsys.com/full-disclosure-charter.html
Current thread:
- Re: ASN.1 telephony critical infrastructure warning - VOIP, (continued)
- Re: ASN.1 telephony critical infrastructure warning - VOIP jan . muenther (Feb 18)
- RE: ASN.1 telephony critical infrastructure warning - VOIP David Wilson (Feb 23)
- Re: ASN.1 telephony critical infrastructure warning - VOIP 3APA3A (Feb 17)
- Re: ASN.1 telephony critical infrastructure warning - VOIP daniel uriah clemens (Feb 17)
- Re: ASN.1 telephony critical infrastructure warning - VOIP Florian Weimer (Feb 17)
- Re[2]: ASN.1 telephony critical infrastructure warning - VOIP 3APA3A (Feb 18)
- Re: ASN.1 telephony critical infrastructure warning - VOIP RJ Auburn (Feb 17)
- Re: ASN.1 telephony critical infrastructure warning - VOIP Michael H. Warfield (Feb 17)
- Re: ASN.1 telephony critical infrastructure warning - VOIP RJ Auburn (Feb 20)
- RE: ASN.1 telephony critical infrastructure warning - VOIP John LaCour (Feb 17)
- Re: ASN.1 telephony critical infrastructure warning - VOIP Joseph M Hoffman (Feb 19)