U.S. Government Issues Report on VoIP Security Holes

ranson writes "PC World is reporting on VoIP technology's threat of being manipulated by hackers, through call interception and DoS attacks on users' internet connections. While these threats are nothing new, the article cites an interesting government report on the topic, as well as its author, who believes a VoIP user's best protection is security by obscurity."

Comments

VOIP calls aren't encrypted?

[Motherfucking Shit]

From the article:

Intercepting Internet traffic is not new. Neither is DoS. But unlike more secure Internet transactions such as your Web connection for online banking, VoIP calls are not encrypted. That makes them susceptible to tapping.

This amazes me, I can't believe that the calls are floating around in raw audio. Would a little encryption add so much overhead that it would bog down the system? Or is this due to CALEA or other laws?

Re:VOIP calls aren't encrypted?

[Spetiam]

Skype says its calls are encrypted.

The calls... are highly secure with end-to-end encryption.

Whether their scheme is snake oil or for real, I don't know, as I can't find any documentation on it, much less source code.

Re:VOIP calls aren't encrypted?

[Bananatree3]

According to Skype's FAQ, all of their VoIP calls are encrypted:

Calls between Skype software users (PC-to-PC calls) are secure and encrypted. Calls to standard telephone or mobile numbers are encrypted until they reach public switched telephone network. Note that in a conference call where one participant is a PSTN (regular telephone or mobile phone) number/phone number, the padlock icon will not appear indicating that the call is not encrypted.

Re:VOIP calls aren't encrypted?

[IWannaBeAnAC]

If there is no documentation, then it is almost certainly snake oil.

Anyway, it is hard to imagine the FBI allowing ordinary consumers to have encryption they cannot break on their telephone calls. Moderately easy to break, but obscure, encryption is exactly what they would be looking for. 99% of criminals will be too dumb to break it, and the other 1% are needed to justify the homeland security budget.

Re:VOIP calls aren't encrypted?

[CodeBuster]

The Rijndael algorithm, with is now the federal advanced encryption standard (AES), is a fast symmetric block cipher which is both public domain and spreading quickly in use. It would not be difficult for the phones to use a public key scheme such as RSA to exchange a session key for Rijndael. The FBI doesn't waste their time intercepting your network traffic and cracking the encryption by brute force computation. They simply bug the keyboard or the room and recover your key. Why waste time picking a complicated lock when you can easily steal the key?

Re:VOIP calls aren't encrypted?

[Talennor]

CALEA says:

"ENCRYPTION- A telecommunications carrier shall not be responsible for decrypting, or ensuring the government's ability to decrypt, any communication encrypted by a subscriber or customer, unless the encryption was provided by the carrier and the carrier possesses the information necessary to decrypt the communication."

Which in my first glance at this means that VoIP can be encrypted, though if the carrier handles too much of the private key generation, which would be necessary for any non-technical user, the carrier must keep the key for law enforcement use. (I'm thinking that a standalone VoIP phone would need a factory generated key on EEPROM, though software VoIP could use your average PC to generate a key itself.) But then again I'm not even sure if this applies to VoIP since this isn't exactly a service I'm currently familiar with. I'll note though that this is the only place "encryption" came up in a search of the law itself, so there's not much more to look at than the above quote. However, what the FBI and FCC have done in regulations may be a totally different matter. Can anyone clear this up more or is it just a regulatory mess?

Re:VOIP calls aren't encrypted?

[Anonymous Coward]

Any system which hides key management completely is snake oil, to a certain extent. Encryption without authentication is useless, and the best authentication you can get with completely hidden key management is that an attacker has to be in the middle from the start and all the time to be undetectable. Better than nothing, but not really secure either. The achievable level is about the same as an SSH account where you never check if the server fingerprint is OK.

Discussed on the Vonage VoIP Forum

[kamikaze-Tech]

This has been discussed at great lengths on the Vonage VoIP Forum here: http://www.vonage-forum.com/ftopic5604.html and also here: http://www.vonage-forum.com/ftopic3422.html

99 Pages, and a bitch aint one

[MikeSingee]

Chances of slashdoters reading that 99 page government report are about the same as VoIP being secure.

Gun in a field

[deathcloset]

Security through obscurity is one of those strange concepts.

Imagine every person in the world standing in a gigantic field. In the direct center of everyone is a rifle pointed at the sky.

When the rifle fires, the bullet will go up and then come down and hit some poor sap. But if one were standing in that crowd one could virtually count one's self out as being crowned that sap.

Virtually, but not completely.

That's the problem with security by obscurity. Sure it lowers the chances of being hit. But it's not really security at all.

Is it?

We need dedicated boxes

[delirium of disorder]

As a former phreaker kiddie, http://angelfire.com/linux/the1 I know how trivial it is to "tap" or disable someone's phone with physical access to the outside of their home or the TNI in their neighborhood. This is not a major threat, because someone whould have to directly be targeting your phone to 0wn it...and if you knew people (non-government) were after your phone conversations, you can put a lock on the grey customer access box on your house, and ask your CO to secure your TNI. Perhaps someone could theoretically compromise the CO's switching equiptment, but that required either good social engneering or real leet skills. But your phone is just your phone, nothing else, so attacks are limited.

VOIP is actually more physically secure then PSTN. You can't just hook a speaker up to a DSL line and hear the conversation on it. The problem is, your computer, and every router between you and your VOIP provider, is a general purpose device. Other people and services have access to it for all kinds of legitimate reasons; each of these provides places where people/programs can input data that can potentially directly effect your voice communications or get privilage escilation on the device and indirectly effect it. ANY security person knows to be wary of input! And think of all the ways of getting input to (and theoretically compromising) a PC. What we need is a dedicated physical console for VOIP (a small linksys network device running OpenBSD or Linux and asterix sounds good). The actual VOIP data should be sent through an SSH tunnel or some kind of VPN.