CVE-2026-59220

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/open-webui/open-webui/commit/61a26722155ec6ee1b629cf8dfcf975098c18331	Patch
https://github.com/open-webui/open-webui/releases/tag/v0.10.0	Product Release Notes
https://github.com/open-webui/open-webui/security/advisories/GHSA-ffpj-xv5c-p3gw	Exploit Mitigation Vendor Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-ffpj-xv5c-p3gw	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-09 17:17

Updated : 2026-07-10 18:15

NVD link : CVE-2026-59220

Mitre link : CVE-2026-59220

CVE.ORG link : CVE-2026-59220

JSON object : View

Products Affected

openwebui

open_webui

CWE

CWE-1333

Inefficient Regular Expression Complexity

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