CVE-2026-70490: Open WebUI: Unapproved accounts can open terminal sessions via a WebSocket auth path missing the role check
Summary The terminal WebSocket route authenticates its own first-message JWT instead of going through the HTTP dependency chain, and never applies the role check that getverifieduser enforces on every HTTP terminal route. An account whose role is pending, meaning registered but not approved, or approved and later deactivated back to pending, can therefore open an interactive terminal session that the HTTP terminal endpoints would refuse. The missing control is the verified-user role gate, not the terminal access grants, which are evaluated correctly.
Preconditions At least one terminal server must be configured, which is off by default, and its access grants must cover the account: either public read (principalid: "") or a group the account still belongs to. The attacker needs a valid, unexpired JWT for a pending account and the terminal server id. Both are obtainable by an account that registered while approvals are pending, or by one that held access and was deactivated, since deactivation sets the role to pending without revoking the token, which lasts four weeks by default. Deployments with no terminal server configured, or whose terminal grants are admin-only, are not affected.
Impact A deployment loses the account-approval boundary for terminal access. An unapproved or deactivated account gets interactive shell access, file browsing and terminal-backed tooling in the terminal environment, for as long as its token remains valid. Because the HTTP terminal routes correctly reject the same account, the two planes disagree, so an administrator who deactivates a user sees access revoked over HTTP while the WebSocket keeps working. The terminal access grants themselves are not bypassed: an account with no grant is still refused, so this only widens access to terminals already shared broadly or with a group the account remains in.
Fix Fixed in v0.11.0 by https://github.com/open-webui/open-webui/pull/27537. Token decoding, revocation checking, user lookup and the role check are consolidated into a single getverifieduserbytoken helper, and both the terminal WebSocket route and the Socket.IO handshake now go through it. The role set lives in one constant shared with the HTTP gate so the two cannot drift apart again. Upgrading fully resolves the issue; no configuration change is required.
Root cause Affected component: backend/openwebui/routers/terminals.py, the resolveauthenticatedconnection helper backing the /{serverid}/api/terminals/{sessionid} WebSocket route. Affected setup: every build from v0.8.8 onward, since the route was introduced there.
WebSocket handshakes cannot use FastAPI dependencies, so this route reimplemented authentication inline. The reimplementation reproduced the parts that are visible in the token, that it decodes and that the user row exists, and silently dropped the part that lives in the database row, the role check. Authorization then ran on two independent code paths with no shared definition of what an authenticated user is, and only one of them was updated when the role gate was introduced.
Credits Reported by @rexpository.
Other sources
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.8.8 until 0.11.0, the terminal WebSocket route in backend/openwebui/routers/terminals.py authenticated its own first-message JWT and never applied the verified-user role gate that getverifieduser enforces on HTTP terminal routes. An account whose role is pending, including a registered but unapproved account or an account deactivated back to pending, can open an interactive terminal session when at least one terminal server is configured and its access grants cover the account. This loses the account-approval boundary for terminal access while the HTTP terminal routes correctly reject the same account. This issue is fixed in 0.11.0.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
pip/open-webuito a version that resolves this vulnerability.Fixed in 0.11.0 - Upgrade
Upgrade
backend/open_webui/routers/terminals.pyto a version that resolves this vulnerability.Fixed in 0.11.0Patch https://github.com/open-webui/open-webui/pull/27537
Event History
Frequently Asked Questions
What is the severity of CVE-2026-70490?
The severity of CVE-2026-70490 is classified as medium with a CVSS score of 6.3.
What is the risk associated with CVE-2026-70490?
CVE-2026-70490 has a risk score of 46, indicating a potential threat to security.
How do I fix CVE-2026-70490?
To fix CVE-2026-70490, ensure proper validation of JWTs through the HTTP dependency chain and implement role checks consistently.
What software is affected by CVE-2026-70490?
CVE-2026-70490 affects the pip/open-webui software.
What does the authentication flaw in CVE-2026-70490 lead to?
The authentication flaw in CVE-2026-70490 can potentially allow users with a 'pending' role to access restricted features without proper verification.