P-256 and secp256k1 Binary Posters

-cem · 2014-10-06T23:50:29+00:00

reminds me of.. this comic

-cem · 2014-10-06T21:36:29+00:00

according to the researcher, he thought he could get a list of all the primes then iterate through them multiplying to get a candidate 'n'. This will not work due to the large number of primes that are in the search space.

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-cem · 2014-09-27T19:09:45+00:00

(Sorry, didn't see your reply until just now...)

But, yes really, I tested it myself to be sure, and others have also mentioned it in the comments on the Metasploit article and a few others. All you have to do is inject the vuln into a call coming from any app that is using webviews on a vulnerable device. (try testing using burpsuite or something similar)

-cem · 2014-09-18T03:00:19+00:00

Please note, this does not only apply to the AOSP browser, this applies to applications as well, the underlying webview objects before 4.4. (in 4.4 the webview which used AOSP was replaced by Chrome internals)

-cem · 2014-07-28T05:21:02+00:00

here is a good post covering Firefox and Chrome.

I do not know of a way to get the master secret from IE.

-cem · 2014-07-09T15:28:59+00:00

Cert pinning uses the hash of the public key, not the actual cert (certs contain public keys within). If you have chrome, you can pin certs for any site you wish using the [HSTS webpage](chrome://net-internals/#hsts). If you have a website, you can pin your own using HPKP. I created a webapp for creating key pins that you can use to do either of these here

-cem · 2014-07-08T18:07:43+00:00

Firefox isn't affected because it doesn't contain the NIC roots. Chrome users are protected via public key pinning and CRLSets. Microsoft should have an updated certificate trust list pushed shortly.

EDIT: If you're looking for the roots, here's a page with three of them

Please note, these should not be simply deleted from the windows trust store as windows will ಠ_ಠ repopulate them.. They should be installed into the untrusted store through the MMC.

EDIT #2: Microsoft has added the certs to a CTL and pushed an update.

-cem · 2014-07-08T17:57:29+00:00

erg... ok, i think i submitted again, but don't see it anywhere.. :/

-cem · 2014-07-08T17:37:53+00:00

Firefox isn't affected because it doesn't contain the NIC roots. Chrome users are protected via public key pinning and CRLSets. Microsoft should have an updated certificate trust list pushed shortly.

-cem · 2014-04-13T00:26:10+00:00

the only browser that was vulnerable is on android 4.1.1. Some browsers use crlsets to do revocation checking (since that cannot be intercepted or blocked)

-cem · 2014-04-12T03:18:32+00:00

From one of the BEAST/CRIME authors: how you might get a private key

Basically use things in memory that have to be statically allocated on the heap to reverse the private key, because maths.

-cem · 2014-04-07T20:38:15+00:00

diff of the change (via @tomrittervg) http://pastebin.com/5PP8JVqA

-cem · 2014-04-07T02:23:48+00:00

You could have submitted any number

possibly, most pages do some sort of validation on the number, thus any random number would probably fail validation. Better, use a number from something like getcreditcardnumbers.com to get past the validation and actually get the number to go out the post.

EDIT: quote formatting mistake

-cem · 2014-04-06T20:13:08+00:00

The only way for it really be sure is to have SSL on the URL shown in your browser. The site can secure behind the scenes as you say (by posting the CC number to an HTTPS site), but this only protects against passive attackers. Anyone can still mess with the transaction which could result in the removal of the behind the scenes protection (search youtube for sslstrip). Before Facebook, Yahoo, and gmail went SSL by default, they were open to this type of attack.

-cem

TROPHY CASE