Openwebui: Security Vulnerabilities
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.8.11 until 0.11.1, src/lib/components/chat/FileNav/PortPreview.svelte rendered terminal port content in an iframe sandbox containing both allow-scripts and allow-same-origin. Because the terminal proxy serves that content from the Open WebUI origin, an authenticated user with access to a shared terminal server could host script on a previewed port and take over a victim's account when the victim opened the preview. This issue is fixed in version 0.11.1.
CVSS Score
8.7
EPSS Score
0.002
Published
2026-09-09
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.6 until 0.11.1, SafePlaywrightURLLoader in backend/open_webui/retrieval/web/utils.py validated a user-controlled hostname in Python and then let the Playwright browser resolve it again in the sync and async request interceptors. An authenticated user controlling authoritative DNS could return a public address to validation and an internal address to the browser, exposing responses from internal services or cloud metadata through web search or URL ingestion. This issue is fixed in version 0.11.1.
CVSS Score
7.7
EPSS Score
0.002
Published
2026-09-09
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.6.41 until 0.11.1, get_user_by_oauth_sub and get_user_by_scim_external_id in backend/open_webui/models/users.py used JSON contains matching that compiled to SQL LIKE substring matching on SQLite. An OAuth subject containing percent or underscore wildcard characters could resolve to a different stored identity, potentially selecting an administrator account and issuing the attacker that account's session; PostgreSQL deployments were not affected. This issue is fixed in version 0.11.1.
CVSS Score
8.1
EPSS Score
0.004
Published
2026-09-09
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, backend/open_webui/models/calendar.py stored the calendar event meta.alert_minutes value without type validation and the shared upcoming-event scheduler compared that value numerically. An authenticated user with the calendar permission could store a non-numeric alert_minutes value that raised an exception and aborted the instance-wide alert pass, suppressing all users' reminders while the event remained in the lookahead window. This issue is fixed in version 0.11.1.
CVSS Score
4.3
EPSS Score
0.003
Published
2026-09-09
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.10.0 until 0.11.1, POST /api/v1/folders/{id}/update/parent allowed a user to place a folder under itself or one of its descendants, while the folder tree walks used by DELETE /api/v1/folders/{id} and POST /api/v1/folders/{id}/read did not track visited folder identifiers. An authenticated user could persist a parent cycle and start a request that consumed CPU and memory indefinitely, with the condition remaining stored until repaired. This issue is fixed in version 0.11.1.
CVSS Score
4.3
EPSS Score
0.003
Published
2026-09-09
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, role synchronization in backend/open_webui/routers/auths.py and backend/open_webui/utils/oauth.py updated an administrator's database role without invalidating the user record cached by backend/open_webui/socket/main.py. An administrator demoted through a trusted role header or OAuth role mapping could keep an already-open Socket.IO connection and continue reading or editing every user's collaborative notes until that connection closed. This issue is fixed in version 0.11.1.
CVSS Score
6.5
EPSS Score
0.003
Published
2026-09-09
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.6.27 until 0.11.1, backend/open_webui/utils/tools.py captured a cookie jar from the enclosing connection loop instead of binding it to each external tool callable. When multiple tool servers were attached and a session or system OAuth connection was processed last, a request to a different server configured for bearer authentication could include the calling user's Open WebUI session cookies, allowing that server's operator to reuse the session and take over the account. This issue is fixed in version 0.11.1.
CVSS Score
6.8
EPSS Score
0.003
Published
2026-09-09
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, the unauthenticated POST /oauth/backchannel-logout handler in backend/open_webui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout token. Each request repeated uncached network fetches, and the signing-key lookup blocked the async event loop, so requests carrying invalid tokens could stall the single-worker instance and amplify traffic to the identity provider when ENABLE_OAUTH_BACKCHANNEL_LOGOUT was enabled. This issue is fixed in version 0.11.1.
CVSS Score
7.5
EPSS Score
0.004
Published
2026-09-09
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. In 0.10.2 and earlier, the GET /api/v1/tools/, GET /api/v1/tools/list, and GET /api/v1/tools/id/{id} endpoints in backend/open_webui/routers/tools.py returned full Python tool source to authenticated non-admin read-only users. ToolResponse deliberately omitted source and specs, but ToolUserResponse permitted extra fields and handlers spread a full tool model dump into the response, re-admitting omitted fields. A non-admin with a read grant can obtain another user's server-side tool source, which commonly embeds hard-coded API keys, credentials, and internal service URLs. This issue is fixed in 0.11.0.
CVSS Score
6.5
EPSS Score
0.003
Published
2026-08-04
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.
CVSS Score
8.7
EPSS Score
0.003
Published
2026-08-04