CVE-2011-4815
CVE-2011-4815 is a high-severity vulnerability in Ruby-lang Ruby with a CVSS 2.0 base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.
Key facts
- Severity: High (CVSS 2.0 base score 7.8)
- EPSS exploit prediction: 4% (90th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Ruby-lang Ruby
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2011-4815?
- 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.
- How severe is CVE-2011-4815?
- CVE-2011-4815 has a CVSS 2.0 base score of 7.8, rated high severity.
- Is CVE-2011-4815 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2011-4815?
- CVE-2011-4815 primarily affects Ruby-lang Ruby. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2011-4815?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2011-4815 published?
- CVE-2011-4815 was published on 2011-12-30 and last updated on 2026-06-16.
References
- http://archives.neohapsis.com/archives/bugtraq/2011-12/0181.html
- http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/391606
- http://jvn.jp/en/jp/JVN90615481/index.html
- http://jvndb.jvn.jp/ja/contents/2012/JVNDB-2012-000066.html
- http://lists.apple.com/archives/security-announce/2012/May/msg00001.html
- http://rhn.redhat.com/errata/RHSA-2012-0069.html
- http://rhn.redhat.com/errata/RHSA-2012-0070.html
- http://secunia.com/advisories/47405
- http://secunia.com/advisories/47822
- http://support.apple.com/kb/HT5281
- http://www.kb.cert.org/vuls/id/903934
- http://www.nruns.com/_downloads/advisory28122011.pdf
- http://www.ocert.org/advisories/ocert-2011-003.html
- http://www.ruby-lang.org/en/news/2011/12/28/denial-of-service-attack-was-found-for-rubys-hash-algorithm/
- http://www.securitytracker.com/id?1026474
- https://exchange.xforce.ibmcloud.com/vulnerabilities/72020
Affected products (5)
- cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*
- cpe:2.3:a:ruby-lang:ruby:1.8.7-p299:*:*:*:*:*:*:*
- cpe:2.3:a:ruby-lang:ruby:1.8.7-p302:*:*:*:*:*:*:*
- cpe:2.3:a:ruby-lang:ruby:1.8.7-p330:*:*:*:*:*:*:*
- cpe:2.3:a:ruby-lang:ruby:1.8.7-p334:*:*:*:*:*:*:*
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