CVE-2026-70492

Medium

Elevated severity or exploit probability.

CVSS base

8.7 HIGH

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

EPSS — probability of exploitation (30 days)

0.3%

26.7th percentile

CISA KEV

Not listed

Weakness / dates

CWE-79

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

CVSS breakdown

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

Attack Vector	N	Network
Attack Complexity	L	Low
Privileges Required	L	Low
User Interaction	R	Required
Scope	C	Changed
Confidentiality	H	High
Integrity	H	High
Availability	N	None

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 0.10.0 until 0.11.0, src/lib/components/chat/Messages/Markdown/KatexRenderer.svelte could store and render a chat message whose math block makes KaTeX fail with a stack overflow instead of a parse error. The catch branch fell back to inserting the original math source into the page as HTML through {@html} rather than as text, so script in the message runs in the browser of whoever views it, including shared chats and channels. The viewer's session token in localStorage can be stolen, and an administrator viewer can have their account taken over. This issue is fixed in 0.11.0.

Affected

openwebui

References

Official: NVD · CVE.org