CVE-2026-70482

Name of the Vulnerable Software and Affected Versions Open WebUI versions 0.8.0 through 0.10.9

Description When the ENABLE OAUTH TOKEN EXCHANGE variable is set to True, the endpoint /oauth/{provider}/token/exchange (also identified as POST /api/v1/auths/oauth/{provider}/token/exchange) fails to verify which OAuth client a provided access token was issued to. The system validates the token by calling the provider userinfo endpoint, which only confirms if a token is valid but not its intended client. This allows an attacker who possesses a valid access token for a victim—obtained through an unrelated OAuth application registered with the same provider—to exchange it for an Open WebUI session. This leads to full account takeover, including administrative access if the victim is an administrator. The issue is particularly prevalent with providers like Google, GitHub, and Okta in default configurations. The vulnerability exists within the token exchange function in backend/open webui/routers/auths.py.

Recommendations Update to version 0.11.0 and configure the OAUTH TOKEN EXCHANGE TRUSTED CLIENT IDS environment variable to define a list of trusted client IDs. For providers that do not support RFC 7662 token introspection, such as Google, Microsoft Entra ID, GitHub, and Feishu, the token exchange feature should be disabled by setting ENABLE OAUTH TOKEN EXCHANGE=False.