CVE-2026-70482

Medium

Elevated severity or exploit probability.

CVSS base

8.1 HIGH

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

EPSS — probability of exploitation (30 days)

0.3%

27.3th percentile

CISA KEV

Not listed

Weakness / dates

CWE-287

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

CVSS breakdown

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

Attack Vector	N	Network
Attack Complexity	L	Low
Privileges Required	N	None
User Interaction	R	Required
Scope	U	Unchanged
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 0.8.0 until 0.11.0, when ENABLE_OAUTH_TOKEN_EXCHANGE=True, /oauth/{provider}/token/exchange accepts a raw provider access token and validates it by calling the provider userinfo endpoint without confirming which OAuth client the token was issued to. Anyone holding an access token minted for any client registered with the same provider could exchange it for an Open WebUI session as that token user, including applications the operator does not control and has never authorized. This issue is fixed in 0.11.0.

Affected

openwebui

References

Official: NVD · CVE.org