Bugtraq mailing list archives
Re: Jetty Session ID Prediction
From: Amit Klein <aksecurity () gmail com>
Date: Tue, 06 Feb 2007 07:04:59 +0200
Michal Zalewski wrote:
On Mon, 5 Feb 2007, NGSSoftware Insight Security Research wrote:Jetty generates a 64-bit session id by generating two 32-bit numbers in this way, so we end up with an encoded 64-bit integer. By decoding the integer and splitting it into its two component 32-bit integers, we can easily brute-force the generator's internal state.Why on earth would you want to brute-force it? http://www.springerlink.com/content/9jkp3179mj6fwh6m/s http://dsns.csie.nctu.edu.tw/research/crypto/HTML/PDF/C89/138.PDF
I don't think that the method described in the paper you referenced above is applicable as-is, because the method requires that the state of the PRNG is known (the coefficients aren't), while in our situation, the coefficients are known, but the state isn't known in fullness (only 32 bits out of the 48 are known).
-Amit
Current thread:
- Jetty Session ID Prediction NGSSoftware Insight Security Research (Feb 05)
- Re: Jetty Session ID Prediction Amit Klein (Feb 05)
- Re: Jetty Session ID Prediction Michal Zalewski (Feb 05)
- Re: Jetty Session ID Prediction Amit Klein (Feb 06)
- Re: Jetty Session ID Prediction Michal Zalewski (Feb 06)
- Re: Jetty Session ID Prediction Amit Klein (Feb 06)
- <Possible follow-ups>
- Re: Jetty Session ID Prediction Chris Anley (Feb 06)
- Re: Jetty Session ID Prediction Amit Klein (Feb 06)
- Re: Jetty Session ID Prediction Chris Anley (Feb 07)
- Re: Jetty Session ID Prediction Michal Zalewski (Feb 06)
- Re: Jetty Session ID Prediction Amit Klein (Feb 06)