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Comment by drivebyacct2 | Hacker News Reader

I don't get it, unless Snowden's published his public key somewhere and Wired has some really, really important information for him?

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The reason you would advertise a page like this is to get lots of people to visit it. It gives Snowden the ability to look like any of the other (tens?) of thousands of people who visit the URL in the next little while.

The Snowden could use Tor to access the website.

Also, there's no other way to get the message to Snowden unless you give it publicity. If he browses the Internet for news, he will find there's a message from Wired for him.

If you were hiding from the NSA.... I'd avoid browsing the internet for a while...

If he's using Tor, and not login in in any site, how are they going to know it's Snowden?

To be fair he's not really hiding...

Tor is only safe to a degree. Probabilistic flow analysis is a real threat.

Thanks for the comment. I saw this story’s presence on HN as a complete waste of space until now.

I imagine anything to do with Snowden pales in comparison to getting lots of people to visit it so they can get ad revenue.

More likely that it's a publicity stunt, raising awareness of strong encryption that the NSA (probably) can't crack yet.

yeah, I was wondering about how strong GPG was. Back in the day, i.e. the 90's, the assumption was it would take years for then-current NSA supercomputers to factor the keys. Nowadays, with all sorts of new attacks, analyses, and cheap as hell compute time, I would wager that time requirement has gone significantly down.

AFAIK, the current publicly-known record for breaking RSA keys is the factorization of RSA-768 in 2010: http://eprint.iacr.org/2010/006.pdf That paper says it took about 1500 CPU-years to break a 768-bit key, and that the difficulty increases 1000x for each additional 256 bits of key length.

For a back-of-the-envelope cost estimate, I'm going to assume that there have been no major theoretical breakthroughs in the last couple of years, and that the machines they used were roughly equivalent to an EC2 "medium" instance. That puts the cost of breaking a 768-bit key, using spot instances for cost-efficiency, at about US$200k.

That sounds small, but encryption/decryption are still reasonably efficient with larger keys, while factorization becomes vastly harder. Breaking a 2048-bit key would take something like 200 quadrillion dollars worth of CPU time. A 4096-bit key, like the one used for this message, would be vastly more secure than that.

Assuming there's no known exploit. The NSA might know of an exploit for that algorithm.

Maybe the message is another encrypted message with a different algorithm?

At the moment, the NSA still permits use of 2048-bit RSA for classified information up to SECRET. It would be highly questionable for them to do so if they knew of easily exploitable weaknesses, as they're taking the chance that other governments won't find them.

Remember, the NSA's mandate is twofold: They are a signals intelligence agency, but they are also charged with protecting government communications, much of which occur with commercially-available cryptography.

RSA does make people nervous for some valid reasons, and that's why there's a gradual transition to ECC underway, but there's little reason to expect a practical attack on RSA at 2048+ bits in the near term.

Absent an operational error on the part of Wired or Snowden, I seriously doubt the NSA will be decrypting that message in Snowden's lifetime, and almost certainly not before changes in the political climate.

That's not the only form of "exploit" http://www.scip.ch/en/?vuldb.2721

Uh, the existence of a buffer overflow (which doesn't even cause disclosure of an encrypted message) has nothing to do with the strength of the RSA algorithm, which is what the comment I replied to was talking about.

You're missing the more obvious form of attack http://lists.gnupg.org/pipermail/gnupg-announce/2006q4/00024...

I remember 768 bit asymetric keys in the mid 90's, and the paranoid had perhaps a 1024 bit key (I'm not very paranoid, and I got a 2048 bit key before 2000). A 768 bit RSA key was factored in 2009; the NSA could probably do it earlier. The default now is 2048 bits, and the key used by Wired is 4096 bits.

That's a lot of doublings of the difficulty to brute force a key. 2^3328 increase in difficulty.

RSA factoring does not increase with keysize increases like you might expect. Factoring, while still very hard, is much better than brute-force and continues to see improvements.

Hm, unfortunate that those who know what it is will recognize it and not think that and the rest will be confused and close the tab and move on. And the comments (on the Wired article) aren't remotely helpful.

Snowden called himself Verax[1]. Anyone who wants to send a message to Snowden* can just:

    $ gpg --keyserver pgp.mit.edu --recv-keys 79DEBE35
    $ gpg --encrypt --sign --armor --recipient 79DEBE35

and post it publicly; perhaps on Pastebin.

[1]: http://www.washingtonpost.com/world/national-security/code-n...

*assuming you believe the key is authentic

79DEBE35 is a key in the possession of Wired, I'm sure they'll enjoy passing your message on the the NSA via their parent media giant.

Edit: Also, it's not very hard to generate a different key with signature 79DEBE35, and put it on the key servers. gpg's displaying of such short abbreviations for keys is one the worst parts of its UI.

>79DEBE35 is a key in the possession of Wired

How do you know this?

It was the signing key on Wired's broadcast.

So? You can download my public key and encrypt something with it... and only I'll be able to read it with my private key.

It's still "my" key even though you're signing or rather encrypting a message with it.

I believe some people, myself included initially, misinterpreted the "encrypted with" key as being the sender's key rather than the recipient's.

We don't know who that key belongs to for sure, of course, but it could be Snowden's.

I find all this public key and private key concept is confusing to general people. A private key is an actual key that you can use to unlock an encrypted message. A public key is actually a lock that you gave someone so that he can use to encrypt message and only you can open it.

The message posted on Wired is encrypted with that key.

EDIT: While what I said was technically true, in that it is encrypted with the 79DEBE35 key, that's not Wired's key, it's the recipient's key.

One could say it was encrypted to the 79DEBE35 key.

The way this thread is going, one probably ought to say that or otherwise imply/explain it :S

Both valid points; I have no way to verify that's an authentic key.

> Edit: Also, it's not very hard to generate a different key with signature 79DEBE35, and put it on the key servers. gpg's displaying of such short abbreviations for keys is one the worst parts of its UI.

Yup: http://www.asheesh.org/note/debian/short-key-ids-are-bad-new...

You can naturally use longer fingerprint to confirm keys. pub 1024D/274EF626 2006-07-25 [expires: 2046-07-15] Key fingerprint = 166C 5F6B 8808 A9BE B2B4 F265 AE02 7784 274E F626

* That's a pretty big assumption now isn't it.

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