CVE-2026-70493

Low

No strong exploitation signal.

CVSS base

6.5 MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS — probability of exploitation (30 days)

0.3%

23.5th percentile

CISA KEV

Not listed

Weakness / dates

CWE-1333

Published 2026-08-04 · modified 2026-09-18

CVSS breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector	N	Network
Attack Complexity	L	Low
Privileges Required	L	Low
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	N	None
Integrity	N	None
Availability	H	High

Timeline

2026-08-04 — Published (NVD)
2026-09-18 — Last modified (NVD)

Description

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.6 until 0.11.0, the built-in knowledge search path in backend/open_webui/tools/knowledge_fs.py and backend/open_webui/tools/builtin.py let a chat participant choose a pattern used to grep knowledge files. Patterns containing regex metacharacters were compiled with Python's backtracking re engine and run against every line of every reachable file with no time limit, so a crafted pattern such as (x|x)*y and one matching uploaded file line can pin one CPU core and block the event loop. This causes availability impact for every other user of the affected worker. This issue is fixed in 0.11.0.

Affected

openwebui

References

Official: NVD · CVE.org