{"cve":"CVE-2023-22795","nvd":{"published":"2023-02-09T20:15:11.420","modified":"2026-10-24T13:10:00.147","status":"Modified","description":"A regular expression based DoS vulnerability in Action Dispatch <6.1.7.1 and <7.0.4.1 related to the If-None-Match header. A specially crafted HTTP If-None-Match header can cause the regular expression engine to enter a state of catastrophic backtracking, when on a version of Ruby below 3.2.0. This can cause the process to use large amounts of CPU and memory, leading to a possible DoS vulnerability All users running an affected release should either upgrade or use one of the workarounds immediately.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-1333","CWE-400"],"references":["https://discuss.rubyonrails.org/t/cve-2023-22795-possible-redos-based-dos-vulnerability-in-action-dispatch/82118","https://security.netapp.com/advisory/ntap-20240202-0010/","https://www.debian.org/security/2023/dsa-5372","https://discuss.rubyonrails.org/t/cve-2023-22795-possible-redos-based-dos-vulnerability-in-action-dispatch/82118","https://security.netapp.com/advisory/ntap-20240202-0010/"],"products":["debian:debian_linux","rubyonrails:rails"],"source":"nvd","synced_at":"2026-10-24T16:53:27.712498749+00:00"},"epss":{"cve":"CVE-2023-22795","score":0.02278,"percentile":0.82999,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-8xww-x3g3-6jcv","url":"https://osv.dev/vulnerability/GHSA-8xww-x3g3-6jcv","summary":"ReDoS based DoS vulnerability in Action Dispatch","modified":"2025-03-31T13:41:44.379427Z","packages":[{"ecosystem":"RubyGems","name":"actionpack","purl":"pkg:gem/actionpack","ranges":[">=4.0.0.beta1 <6.1.7.1"],"fixed":["6.1.7.1"]},{"ecosystem":"RubyGems","name":"actionpack","purl":"pkg:gem/actionpack","ranges":[">=7.0.0 <7.0.4.1"],"fixed":["7.0.4.1"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}