CVE-2026-59220 | Open WebUI up to 0.9.x Middleware middleware.py incorrect regex

A vulnerability, which was classified as problematic, was found in Open WebUI up to 0.9.x. This impacts an unknown function of the file backend/open_webui/utils/middleware.py of the component Middleware. The manipulation results in incorrect regular expression.

This vulnerability is reported as CVE-2026-59220. The attack can be launched remotely. No exploit exists.