CVE-2023-22796
highpriority · track · 31EPSS 0.017 · 77 %ileDEEURUUSEPSS · scored 2026-10-27
A regular expression based DoS vulnerability in Active Support <6.1.7.1 and <7.0.4.1. A specially crafted string passed to the underscore method can cause the regular expression engine to enter a state of catastrophic backtracking. This can cause the process to use large amounts of CPU and memory, leading to a possible DoS vulnerability.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (24)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2023-0114Ruby on Rails: Mehrere SchwachstellenDeutsch2023-01-17csaf · cert_bundDE
Ein entfernter Angreifer kann mehrere Schwachstellen in Ruby on Rails ausnutzen, um einen Denial of Service Angriff durchzuführen, Daten zu manipulieren und Sicherheitsmaßnahmen zu umgehen.
- WID-SEC-W-2023-2101genua genucenter: Mehrere SchwachstellenDeutsch2023-08-20csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in genua genucenter ausnutzen, um Informationen offenzulegen, Dateien zu manipulieren, um Cross-Site Scripting Angriffe durchzuführen oder um einen nicht näher spezifizierten Angriff durchzuführen.
- GHSA-j6gc-792m-qgm2ReDoS based DoS vulnerability in Active Support's underscore2023-01-18ghsa · osvUS
There is a possible regular expression based DoS vulnerability in Active Support. This vulnerability has been assigned the CVE identifier CVE-2023-22796. Versions Affected: All Not affected: None Fixed Versions: 5.2.8.15 (Rails LTS, which is a paid service and not part of the rubygem), 6.1.7.1, 7.0.4.1 Impact A specially crafted string passed to the underscore method can cause the regular expression engine to enter a state of catastrophic backtracking. This can cause the process to use large amounts of CPU and memory, leading to a possible DoS vulnerability. This affects String#underscore, ActiveSupport::Inflector.underscore, String#titleize, and any other methods using these. All users running an affected release should either upgrade or use one of the workarounds immediately. Releases The FIXED releases are available at the normal locations. Workarounds There are no feasible workarounds for this issue. Users on Ruby 3.2.0 or greater may be able to reduce the impact by configuring Regexp.timeout. Patches To aid users who aren’t able to upgrade immediately we have provided patches for the two supported release series. They are in git-am format and consist of a single changeset. 6-1-Avoid-regex-backtracking-in-Inflector.underscore.patch - Patch for 6.1 series 7-0-Avoid-regex-backtracking-in-Inflector.underscore.patch - Patch for 7.0 series Please note that only the 7.0.Z and 6.1.Z series are supported at present, and 6.0.Z for severe vulnerabilities. Users of earlier unsupported releases are advised to upgrade as soon as possible as we cannot guarantee the continued availability of security fixes for unsupported releases.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (14)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/cve-2023-22796cnnvd
- https://cxsecurity.com/cveshow/CVE-2023-22796/cnnvd
- https://discuss.rubyonrails.org/t/cve-2023-22796-possible-redos-based-dos-vulnerability-in-active-supports-underscore/82116cnnvd
- https://www.auscert.org.au/bulletins/ESB-2023.0694cnnvd
- https://www.auscert.org.au/bulletins/ESB-2023.1365cnnvd
- https://www.auscert.org.au/bulletins/ESB-2023.1542cnnvd
- https://www.auscert.org.au/bulletins/ESB-2023.4366cnnvd
- https://www.debian.org/security/2023/dsa-5372cnnvd
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