GHSA-FFPJ-XV5C-P3GW Open WebUI: ReDoS in skill-mention regexes causes whole-instance DoS on default config

Summary Two regexes in backend/openwebui/utils/middleware.py that parse skill-mention tags backtrack in On² on input that contains . Both run synchronously, on the asyncio event loop, on every chat completion with no feature gate. Because the default deployment is a single uvicorn worker, one suc...

CVE-2026-59220 Open WebUI: ReDoS in skill-mention regexes causes whole-instance DoS on default config

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.2 before 0.10.0, the SKILLMENTIONRE and stripre regular expressions in backend/openwebui/utils/middleware.py parsed skill mentions with overlapping quantifiers, allowing an authenticated chat message...

CVE-2026-59220

Open WebUI (self-hosted AI platform) has a ReDoS in theSkill mention handling. In versions before 0.10.0, the SKILL_MENTION_RE and strip_re regexes in backend/open_webui/utils/middleware.py parsed mentions with overlapping quantifiers, allowing an authenticated user to send a message containing ...

CVE-2026-59220 Open WebUI: ReDoS in skill-mention regexes causes whole-instance DoS on default config

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.2 before 0.10.0, the SKILLMENTIONRE and stripre regular expressions in backend/openwebui/utils/middleware.py parsed skill mentions with overlapping quantifiers, allowing an authenticated chat message...