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Flaws Threaten VoIP Networks?
jdkane writes "CNET News reports that security flaws have been found in products that use VoIP and text messaging, including those from Microsoft and Cisco Systems. What's interesting, in Microsoft's case, is that the Internet Security and Acceleration Server product that's also affected is designed to help protect companies' networks from online attacks. Specifically, a filter used in the server that secures VoIP communications is vulnerable to the flaw."
So it seems they've already fixed the problem.
Should we blame lazy sysadmins for not keeping their systems patched?
Or should we blame Microsoft?
I have been pwned because my
I saw that embeded XP beat out linux for Radio Shacks POS.. Wait tell the hackers get into that system..
Wonder why we are fed-xing all these remote control cars to russia?? Must be popular there..
In Cisco products - they are also vulnerable - and particularly when used as firewalls or edge devices.
But then again it's more fun to blame MS isn't it ;-)
Wow that ought to really bolster a customer's confidence: NOt only are you saying this type of mistake is common in your experience, your excuse is "Hey we're only human"! Uh isn't that why you're supposed to have quality assurance?
I went to the city because I wished to live without deliberation.
Vulnerable (updates available): Cisco and Microsoft
Unknown: Avaya, Fujitsu, Hewlett-Packard, Lucent and Nortel
Safe: Apple, Hitachi, NetBSD, Red Hat and Symantec
Is that a point for Security through open source as the two open products are already in the safe pile?
Never underestimate the dark side of the Source
*walks and stops in one place* Can you hack me now? ... Good.
*walks and stops in one place*
Can you hack me now? ... Good.
Taken all together, VoIP should be deployed very carefully in places where network security is important. You might even run into a case where even if your computer network is completely separate from the Internet, but you use VoIP over the internal LAN via a IP PBX, someone might hack your phone/VoIP endpoint through the encoded voice stream and gain access to your LAN. Stranger things have happened.
Suppose that a new bug were described as a "file sharing security flaw". Now, does that affect Samba? FTP? NFS? Kazaa? File server bots on IRC? One expects good technical reporting to mention the affected services -- or better yet, actual products -- rather than simply describing a general application category.
Specifically, in the VoIP application category, there are two major signaling protocols in use: H.323 and SIP. The last round of "VoIP security flaws" affected SIP software. The current discoveries affect H.323. Describing both as "VoIP flaws" and suggesting that the application domain itself is "threatened" is really quite silly. It is as if someone suggested that a certain bug in IIS and another in Freenet together suggested that "file transfer" on the Internet were threatened.
(For those who don't know much about VoIP: H.323 is the older of the two protocols, and is closer to the "telecoms" way of doing things. It was, IIRC, originally connected to ISDN. SIP is newer, and closer to the "Internet" way of doing things -- if you look at packet captures of it, they look vaguely reminiscent of HTTP, only they're UDP.)
I don't think that this is going to be as large of a problem as Cisco's earlier issues. Although a worm could target home users running IP telephony applications on their PC's, this vulnerability is non-replicating and the potential for abuse is rather limited.
Basically, there are two major Cisco product lines that are affected by this bug. The first is Cisco's VoIP infrastructure products: the Cisco CallManager server, Conferencing Server, Softswitch and IOS-based routers running H.323 services, among others. Except where the public has access to VoIP services over the Internet, these servers and routers are located on the inside of a firewall. In a best-practices network design, all access to these servers and routers is either via the internal LAN or through a secure VPN connection over the Internet (or any other public network, for that matter). I would find it very unusual to have these services available publicly. If I left a Cisco router with POTS access and an easily guessable dial peer on an Internet-accessible LAN, the potential for toll fraud would be enormous (free calls, lots 'o free calls).
The second group of products that are vulnerable are Cisco routers performing NAT and firewall services. Cisco's Content Based Access-Control (CBAC) -- a "dynamic firewall" technology -- is also vulnerable to the H.323 DoS attacks in the same manner as the Microsoft IAS server. Once again, unless H.323 ports are open to unrestricted access from the Internet, routers are not vulnerable from random outside attacks. Traffic that originated from behind the firewall would be able to disrupt services, however it's much easier to apply an access list to track and block the offending traffic than it is to prevent an external DoS attack.
What's my point? I don't see a widespread attack being able to disable servers and routers on a large scale. Unless attacks are originated from inside a corporate firewall, the potential for disrupted services are minimal. I'm sure that large VoIP service providers are scrambling to patch and secure whatever systems possible - however, they are much better equipped to handle this issue than a Mom and Pop business who happens to have a CallManager server (at least we hope).
For people who are running these products, I'm recommending a thorough review of external firewall policies to make sure that there aren't any exposed H.323 ports. I'm also recommending an upgrade when it's feasible, but IMHO, there aren't many situations that would require burning the midnight oil to install patches.
Just my $.02.