- ~> 5.2.8, >= 126.96.36.199
- ~> 6.1.7, >= 188.8.131.52
- >= 184.108.40.206
There is a possible regular expression based DoS vulnerability in Action Dispatch related to the If-None-Match header. This vulnerability has been assigned the CVE identifier CVE-2023-22795.
Versions Affected: All Not affected: None Fixed Versions: 220.127.116.11 (Rails LTS), 18.104.22.168, 22.214.171.124
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.
We recommend that all users upgrade to one of the FIXED versions. In the meantime, users can mitigate this vulnerability by using a load balancer or other device to filter out malicious If-None-Match headers before they reach the application.
Users on Ruby 3.2.0 or greater are not affected by this vulnerability.