Weakness in some certificate authorities
Dec. 31st, 2008 01:14 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
jducoeurSerious Internet geeks may want to take a look at this article in Ars Technica.
Summary: it's been known for a while that the MD5 hash algorithm is a bit weak. Some researchers have used this weakness to create a *really* horrible hack, allowing them to impersonate a major top-level Certificate Authority for cert-signing purposes. They're not saying exactly how the hack works, but the implication is that hackers (using this and other known techniques) could use this to more or less completely impersonate major secure sites, so that users would have no way of knowing that they're talking to a forgery. Very, very, *very* bad.
Moral of the story is that, if you're using MD5 for anything really important, it may be time to move on to better algorithms. With any luck, this will spur all the CAs to do so -- certainly, I would hope that any financial institution would be putting the thumbscrews on its CAs to do so quickly...
Summary: it's been known for a while that the MD5 hash algorithm is a bit weak. Some researchers have used this weakness to create a *really* horrible hack, allowing them to impersonate a major top-level Certificate Authority for cert-signing purposes. They're not saying exactly how the hack works, but the implication is that hackers (using this and other known techniques) could use this to more or less completely impersonate major secure sites, so that users would have no way of knowing that they're talking to a forgery. Very, very, *very* bad.
Moral of the story is that, if you're using MD5 for anything really important, it may be time to move on to better algorithms. With any luck, this will spur all the CAs to do so -- certainly, I would hope that any financial institution would be putting the thumbscrews on its CAs to do so quickly...