Open WebUI 0.11.0 before 0.11.4 compiles user-chosen grep patterns for its knowledge and chat file search tools with a regex engine that expands nested counted repetition unbounded at compile time and caches the result. Authenticated users can have the model call grep_knowledge_files with short nested-repetition patterns, blocking the event loop and exhausting worker memory.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
References 3
https://github.com/open-webui/open-webui/commit/97e013a66169c4fcd7f26ab9e41a4ff…
disclosure@vulncheck.com
https://github.com/open-webui/open-webui/security/advisories/GHSA-gww9-mhgj-pfqh
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/open-webui-0.11.0-before-0.11.4-memory-exh…
disclosure@vulncheck.com