Openwebui: >> Open Webui >> 0.8.12 Security Vulnerabilities
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, POST /api/v1/calendars/events/{event_id}/update validates that the caller has write access to the calendar the event currently belongs to, but does not validate the destination calendar_id supplied in the request body. The model layer then persists the new calendar_id unconditionally. A regular user-role account can therefore create an event in their own calendar and immediately move it into any other user's calendar whose ID they know — bypassing the authorization check that create_event correctly performs. This vulnerability is fixed in 0.9.6.
CVSS Score
4.3
EPSS Score
0.003
Published
2026-06-23
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, the chat message listener allows non-same-origin input:prompt and action:submit messages, so an external site can set prompt text and trigger submitPrompt() in an authenticated victim session. I validated this with a cross-origin attacker page that auto-posted messages and caused unauthorized POST /api/v1/chats/new and POST /api/chat/completions requests containing attacker-controlled prompts. This enables cross-site forced actions and model/tool execution under victim privileges without consent. This vulnerability is fixed in 0.9.6.
CVSS Score
7.1
EPSS Score
0.002
Published
2026-06-23
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, backend/open_webui/utils/oauth.py::_process_picture_url calls validate_url(picture_url) on the initial URL only, then invokes aiohttp.ClientSession.get(picture_url, ...) without allow_redirects=False. aiohttp's default is allow_redirects=True, max_redirects=10; the function does not pass the project's AIOHTTP_CLIENT_ALLOW_REDIRECTS env constant either. An attacker with a valid OAuth IdP identity can therefore submit a public URL that 302-redirects to an internal address and read the internal response body via the attacker's own profile_image_url field. This vulnerability is fixed in 0.9.6.
CVSS Score
8.5
EPSS Score
0.003
Published
2026-06-23
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, the terminal-server reverse proxy in `backend/open_webui/routers/terminals.py` does not fully confine the user-controlled `path` segment before forwarding it to an admin-configured terminal server. An authenticated user who has been granted access to a terminal server can craft `path` values containing encoded `../` traversal sequences that escape the intended path (or policy) scope on that server, reaching unintended endpoints and files on the terminal-server host. Where the terminal server fans requests out to internal services, this also gives SSRF-style reach into those services. This is a separate code path from the `/api/v1/retrieval/process/web` SSRF (GHSA-c6xv-rcvw-v685), with its own input. Two distinct vectors are consolidated here: first, raw path forwarding / single-encoded traversal (original report); and second, a bypass of the subsequently-added `_sanitize_proxy_path` mitigation using double-encoded dots (`%252e%252e`). The attacker-controlled input is the request `path`, supplied by the non-admin user, not anything an administrator configures, so this is not an admin-trust / Rule-9 situation. Version 0.9.6 fixes the issue.
CVSS Score
7.7
EPSS Score
0.005
Published
2026-06-18
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, the channel webhook create/update flow accepts arbitrary profile_image_url values, including data:image/svg+xml;base64,... payloads. The profile image endpoint then decodes and serves this SVG as image/svg+xml without sanitization, allowing attacker-controlled script handlers (for example onload) to execute when the profile-image URL is opened in the browser. This vulnerability is fixed in 0.9.3.
CVSS Score
7.4
EPSS Score
0.002
Published
2026-05-15
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, the audio transcription upload endpoint takes the file extension from the user-supplied filename and saves the file under CACHE_DIR/audio/transcriptions/.. The /cache/{path} route serves these files via FileResponse, which sets Content-Type from the on-disk extension and emits no Content-Disposition. A verified user with the default-on chat.stt permission can upload a polyglot WAV+HTML file named pwn.html and trick any other user into opening the resulting URL — the response comes back as text/html and any embedded <script> runs in the Open WebUI origin. This vulnerability is fixed in 0.9.3.
CVSS Score
8.7
EPSS Score
0.002
Published
2026-05-15
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, the POST /api/v1/notes/{id}/pin endpoint performs a write operation (toggling the is_pinned field) but only checks for read permission. Users with read-only access to a shared note can pin/unpin it, which is a state-modifying action that should require write permission. This vulnerability is fixed in 0.9.3.
CVSS Score
3.5
EPSS Score
0.003
Published
2026-05-15
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, an application-wide Cross-Site Request Forgery (CSRF) vulnerability was found Open-WebUl's image uploading functionality. An attacker can set an image URL to a malicious endpoint, allowing them to perform actions on behalf of a victim user. Any authenticated user can exploit this vulnerability, and any user who views the compromised image (e.g., a profile picture) will unknowingly send a GET request to the attacker-controlled URL. This can lead to cookie theft, denial of service (DoS), or other malicious actions. This vulnerability is fixed in 0.9.3.
CVSS Score
4.6
EPSS Score
0.001
Published
2026-05-15
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, his advisory tracks a regression of the original Excel-preview XSS (CVE-2026-44549). The same root cause — XLSX.utils.sheet_to_html() output rendered via {@html excelHtml} without DOMPurify — was reintroduced sometime after v0.8.0 and is exploitable again This vulnerability is fixed in 0.9.3.
CVSS Score
5.4
EPSS Score
0.002
Published
2026-05-15
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, a Server-Side Request Forgery (SSRF) vulnerability exists in _process_picture_url() in backend/open_webui/utils/oauth.py (line ~1338). The function fetches arbitrary URLs from OAuth picture claims without applying validate_url(), allowing an attacker to force the server to make HTTP requests to internal resources and exfiltrate the full response. This vulnerability is fixed in 0.9.0.
CVSS Score
7.7
EPSS Score
0.004
Published
2026-05-15