Encryption algorithm solved.

[rebellatio 25]

http://www.theverge.com/2017/2/23/14712118/google-sha1-collision-broken-web-encryption-shattered

[greenclaydog 6]

@Staff might want to upgrade from SHA 1 for potential security issues in the future. 

[zhang888 1066]

SHA1 is a hashing and not an encryption algorithm.

The impact of this collision attack is mainly forging file signatures, and it cannot be applied as a network attack to modify or inject traffic into VPN sessions.

HMAC-SHA1 is not vulnerable to this as well.

[OmniNegro 155]

As Zhang said, There is no problem. For those who do not already know, HMAC is a hash applied to the SHA1 hash. And it is done for each and every packet. Your system, even on a slow dial up modem uses a packet for every 1500 bytes or so. So in order to defeat HMAC-SHA1 you would have to not only break it in milliseconds, but also defy the laws of physics to get your fake packet there before the real one.

 

And let us see how long it takes a whole array of supercomputers to break SHA1 alone?

https://security.googleblog.com/2017/02/announcing-first-sha1-collision.html

Here is the important part to note.

• Nine quintillion (9,223,372,036,854,775,808) SHA1 computations in total
• 6,500 years of CPU computation to complete the attack first phase
• 110 years of GPU computation to complete the second phase

That is to do JUST ONE SINGLE hash. Not to break every hash SHA1 can do. That is one. And this absolutely cannot be done before the relevant packet is done and gone forever.

 

You are safe. Relax.

[greenclaydog 6]

 

To be fair, more security would not hurt anyone (I think?) 

 

Reading up on it, this was Google's push to get websites away from SHA1

 

We probably have no reason for concern but...

 

*tin foil hat on*

What Google can do, the NSA might be able to do better

*tin foil hat off* 

[zhang888 1066]

Again, SSL SHA1 keys, which are static, have nothing to do with HMAC-SHA1 in the context VPN traffic.

[greenclaydog 6]

We probably have no reason for concern 

[Khariz 109]

https://www.privateinternetaccess.com/blog/2017/02/private-internet-access-safe-sha-1-security/

[Staff 10014]

Hello,

the following paper is extremely important, because provides mathematical proof that HMAC is a PRF under the sole assumption that the compression function is a PRF. As long as the assumption holds true, as it is until now, after 10 years the paper was written, there is really no reasonable argumentation to grade "security" of HMAC SHA2 over HMAC SHA1. Or even HMAC MD5!

https://cseweb.ucsd.edu/~mihir/papers/hmac-new.pdf

Kind regards

[OpenSourcerer 1441]

Papers are long. Reddit does it shorter.