CVE-2025-61921 | Sinatra up to 4.1.x Header If-Match/If-None-Match redos (ID 19104 / Nessus ID 270281)
A vulnerability, which was classified as problematic, was found in Sinatra up to 4.1.x. This impacts an unknown function of the component Header Handler. Executing manipulation of the argument If-Match/If-None-Match can lead to inefficient regular expression complexity.
This vulnerability is tracked as CVE-2025-61921. The attack can be launched remotely. No exploit exists.
You should upgrade the affected component.