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.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://discuss.rubyonrails.org/t/cve-2023-22795-possible-redos-based-dos-vulnerability-in-action-dispatch/82118 Patch, Vendor Advisory
- https://discuss.rubyonrails.org/t/cve-2023-22795-possible-redos-based-dos-vulnerability-in-action-dispatch/82118 Patch, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 7.5 · rubyonrails, debianNVD modified 2026-10-24 13:10
Affected (CPE criteria) 2
cpe:2.3:a:rubyonrails:rails:*:*:*:*:*:*:*:*cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
References 6
- https://discuss.rubyonrails.org/t/cve-2023-22795-possible-redos-based-dos-vulnerability-in-action-dispatch/82118 Patch, Vendor Advisory
- https://security.netapp.com/advisory/ntap-20240202-0010/
- https://www.debian.org/security/2023/dsa-5372 Third Party Advisory
- https://discuss.rubyonrails.org/t/cve-2023-22795-possible-redos-based-dos-vulnerability-in-action-dispatch/82118 Patch, Vendor Advisory
- https://security.netapp.com/advisory/ntap-20240202-0010/
- https://www.debian.org/security/2023/dsa-5372 Third Party Advisory