{"id":"CVE-2011-4815","url":"https://www.cyber-defence.io/tools/cve/CVE-2011-4815","generatedAt":"2026-10-27T19:49:01.398Z","title":"Ruby (aka CRuby) before 1.8.7-p357 computes hash values without restricting the ability to trigger hash collisions predictably, which allows context-dependent attackers to cause a denial of service (CPU consumption) via crafted input to an application…","description":"Ruby (aka CRuby) before 1.8.7-p357 computes hash values without restricting the ability to trigger hash collisions predictably, which allows context-dependent attackers to cause a denial of service (CPU consumption) via crafted input to an application that maintains a hash table.","published":"2011-12-30T01:55:01.000Z","lastModified":"2026-06-16T23:35:27.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"2.0","score":7.8,"severity":"HIGH","vector":"AV:N/AC:L/Au:N/C:N/I:N/A:C"},"cwe":["CWE-20"],"affected":["ruby-lang/ruby"],"epss":{"score":0.04059,"percentile":0.90586,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (4.06%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"http://archives.neohapsis.com/archives/bugtraq/2011-12/0181.html","source":"cve@mitre.org"},{"url":"http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/391606","source":"cve@mitre.org"},{"url":"http://jvn.jp/en/jp/JVN90615481/index.html","source":"cve@mitre.org"},{"url":"http://jvndb.jvn.jp/ja/contents/2012/JVNDB-2012-000066.html","source":"cve@mitre.org"},{"url":"http://lists.apple.com/archives/security-announce/2012/May/msg00001.html","source":"cve@mitre.org"},{"url":"http://rhn.redhat.com/errata/RHSA-2012-0069.html","source":"cve@mitre.org"},{"url":"http://rhn.redhat.com/errata/RHSA-2012-0070.html","source":"cve@mitre.org"},{"url":"http://secunia.com/advisories/47405","source":"cve@mitre.org"},{"url":"http://secunia.com/advisories/47822","source":"cve@mitre.org"},{"url":"http://support.apple.com/kb/HT5281","source":"cve@mitre.org"},{"url":"http://www.kb.cert.org/vuls/id/903934","tags":["US Government Resource"],"source":"cve@mitre.org"},{"url":"http://www.nruns.com/_downloads/advisory28122011.pdf","source":"cve@mitre.org"},{"url":"http://www.ocert.org/advisories/ocert-2011-003.html","source":"cve@mitre.org"},{"url":"http://www.ruby-lang.org/en/news/2011/12/28/denial-of-service-attack-was-found-for-rubys-hash-algorithm/","source":"cve@mitre.org"},{"url":"http://www.securitytracker.com/id?1026474","source":"cve@mitre.org"},{"url":"https://exchange.xforce.ibmcloud.com/vulnerabilities/72020","source":"cve@mitre.org"},{"url":"http://archives.neohapsis.com/archives/bugtraq/2011-12/0181.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/391606","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://jvn.jp/en/jp/JVN90615481/index.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://jvndb.jvn.jp/ja/contents/2012/JVNDB-2012-000066.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.apple.com/archives/security-announce/2012/May/msg00001.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://rhn.redhat.com/errata/RHSA-2012-0069.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://rhn.redhat.com/errata/RHSA-2012-0070.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://secunia.com/advisories/47405","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://secunia.com/advisories/47822","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://support.apple.com/kb/HT5281","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.kb.cert.org/vuls/id/903934","tags":["US Government Resource"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.nruns.com/_downloads/advisory28122011.pdf","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.ocert.org/advisories/ocert-2011-003.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.ruby-lang.org/en/news/2011/12/28/denial-of-service-attack-was-found-for-rubys-hash-algorithm/","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securitytracker.com/id?1026474","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://exchange.xforce.ibmcloud.com/vulnerabilities/72020","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2011-4815","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}