CVE WatchOct 23, 2026

CVE-2026-109298

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 exp

CVSS

6.5

Medium

EPSS

0.4%

p32

KEV

—

Exploit Today

0-100

Published: Oct 12, 2026 · Last modified: Oct 23, 2026 · CWE-400 · CWE-770

EPSS · 30d

0.4%EPSS · 30 days0.4%

2026-10-132026-10-23

Technical description

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.

Official references

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