CVE-2026-109283 Open WebUI 0.11.1 before 0.11.4 Authorization Bypass via OAuth Token Exchange
Attackers can retain previous high-privilege roles during OAuth token exchange by exploiting flawed role claim validation in Open WebUI.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-109283?
CVE-2026-109283 is a medium-severity authentication bypass vulnerability in open-webui, published on 12 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Open WebUI from 0.11.1 before 0.11.4 contains an authorization bypass in the OAuth token exchange endpoint, which reads role claims only from the provider's userinfo response and keeps the user's existing role when no roles claim is found, ignoring roles sent only in the ID token. Users with a linked account whose identity provider role no longer satisfies the OAuth role policy can send a valid provider access token to POST /api/v1/auths/oauth/{provider}/token/exchange to obtain a session retaining their previous role.
Weakness: CWE-863
Which versions are affected by CVE-2026-109283?
How do I fix CVE-2026-109283?
No fix has been published for CVE-2026-109283 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-109283 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109283 exists.
Sources
Also known as GHSA-2rr4-q6pg-m5g3, GHSA-wr8j-3xx4-g2v5.