CVE-2026-59220
Last modified
CVE-2026-59220 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.2 before 0.10.0, the SKILL_MENTION_RE and strip_re regular expressions in backend/open_webui/utils/middleware.py parsed <$skillId|label> skill mentions with overlapping quantifiers, allowing an authenticated chat message containing <$ without a closing > to trigger quadratic backtracking and block the asyncio event loop. EPSS estimates a 0.29% chance of exploitation in the next 30 days.
Description
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.2 before 0.10.0, the SKILL_MENTION_RE and strip_re regular expressions in backend/open_webui/utils/middleware.py parsed <$skillId|label> skill mentions with overlapping quantifiers, allowing an authenticated chat message containing <$ without a closing > to trigger quadratic backtracking and block the asyncio event loop. This issue is fixed in version 0.10.0.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Openwebui | Open Webui | >= 0.9.2, < 0.10.0 |
References
- https://github.com/open-webui/open-webui/releases/tag/v0.10.0Product, Release Notes
- https://github.com/open-webui/open-webui/security/advisories/GHSA-ffpj-xv5c-p3gwExploit, Mitigation, Vendor Advisory
- https://github.com/open-webui/open-webui/security/advisories/GHSA-ffpj-xv5c-p3gwExploit, Mitigation, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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