This site is the archived OWASP Foundation Wiki and is no longer accepting Account Requests.
To view the new OWASP Foundation website, please visit https://owasp.org
Difference between revisions of "Insufficient Entropy"
(Reverting to last version not containing links to s1.shard.jp)
(Reverting to last version not containing links to www.textrelactrocal.com)
|Line 1:||Line 1:|
Revision as of 18:27, 27 May 2009
This article is a stub. You can help OWASP by expanding it or discussing it on its Talk page.
This is a Vulnerability. To view all vulnerabilities, please see the Vulnerability Category page.
Last revision (mm/dd/yy): 05/27/2009
Vulnerabilities Table of Contents
When an undesirably low amount of entropy is available. Psuedo Random Number Generators are susceptible to suffering from insufficient entropy when they are initialized, because entropy data may not be available to them yet.
- In many case,s a PRNG uses a combination of the system clock and entropy to create seed data. If insufficient entropy is available, an attacker can reduce the size magnitude of the seed value considerably. Furthermore, by guessing values of the system clock, they can create a manageable set of possible PRNG outputs.
- Many PRNG's (/dev/random and /dev/urandom for example) store their last value before shutdown. By using this value at intialization, they can sometimes avoid insufficient or predictable starting entropy.
Related Technical Impacts