CVE-2011-2686

Severity: medium (CVSS 5.0 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2011-08-05 · updated 2026-06-16
Weakness: CWE-310

Description

Ruby before 1.8.7-p352 does not reset the random seed upon forking, which makes it easier for context-dependent attackers to predict the values of random numbers by leveraging knowledge of the number sequence obtained in a different child process, a related issue to CVE-2003-0900. NOTE: this issue exists because of a regression during Ruby 1.8.6 development.

Affected products

Ruby: through 1.8.7-334; 1.8.7-p22, 1.8.7-p71, 1.8.7-p72, 1.8.7-160, 1.8.7-173, 1.8.7-248 (+5)

References

http://lists.fedoraproject.org/pipermail/package-announce/2011-July/063062.html
http://lists.fedoraproject.org/pipermail/package-announce/2011-July/063071.html
http://redmine.ruby-lang.org/issues/show/4338
http://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=31713
http://svn.ruby-lang.org/repos/ruby/tags/v1_8_7_352/ChangeLog
http://www.openwall.com/lists/oss-security/2011/07/11/1
http://www.openwall.com/lists/oss-security/2011/07/12/14
http://www.openwall.com/lists/oss-security/2011/07/20/1
http://www.openwall.com/lists/oss-security/2011/07/20/16
http://www.ruby-lang.org/en/news/2011/07/02/ruby-1-8-7-p352-released/
http://www.securityfocus.com/bid/49015
https://bugzilla.redhat.com/show_bug.cgi?id=722415

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