Open WebUI: Stored XSS in Mermaid Markdown Preview

SummaryOpen WebUI renders Mermaid blocks from Markdown files in the file preview panel and inserts the generated SVG into the DOM using innerHTML.Because Mermaid is configured with securityLevel: 'loose', attacker-controlled Mermaid content can be rendered unsafely in this flow. A working payload...

Open WebUI: Forged chat-file link allows cross-user file read and deletion

SummaryOpen WebUI v0.9.5 lets an authenticated user attach arbitrary fileid values to their own chat message without checking whether they own or can read those files. If the attacker then shares that chat and grants themselves read access, hasaccesstofile treats the victim file as accessible...

PYSEC-2026-2721 Open WebUI BOLA: `search_knowledge_files` Allows Unauthorized Knowledge Base File Enumeration

Summary Open WebUI has a Broken Object Level Authorization BOLA vulnerability in the builtin searchknowledgefiles tool. When native function calling is enabled and the selected model has no attached knowledge bases, an authenticated user can call searchknowledgefiles with an arbitrary knowledgeid...

PYSEC-2026-2695 Open WebUI: Cross-origin postMessage confirmation bypass via action:submit

Summary 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 unauthoriz...

PYSEC-2026-2757 Open WebUI: Stored XSS to Account Takeover via Model Profile Images

Stored XSS to Account Takeover via Model Profile Images in Open WebUI Affected: Open WebUI tags. On the output side, users.py added a MIME allowlist check and X-Content-Type-Options: nosniff. The fix was applied to UserUpdateForm, UpdateProfileForm, and later to ChannelWebhookForm. Three models...

PYSEC-2026-2751 Open WebUI: Path traversal / SSRF in terminal server proxy via encoded path traversal

Summary The terminal-server reverse proxy in backend/openwebui/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...

PYSEC-2026-2761 Open WebUI: Forged model meta.knowledge allows cross-user file read and deletion

Summary Open WebUI lets a user who can create, update, or import workspace models store arbitrary meta.knowledge entries on their model without checking whether they own or can read the referenced files. Open WebUI then treats meta.knowledge entries of type file as an authorization source in two...

PYSEC-2026-2759 Open WebUI: Stored XSS in Mermaid Markdown Preview

Summary Open WebUI renders Mermaid blocks from Markdown files in the file preview panel and inserts the generated SVG into the DOM using innerHTML. Because Mermaid is configured with securityLevel: 'loose', attacker-controlled Mermaid content can be rendered unsafely in this flow. A working paylo...

PYSEC-2026-2763 Open WebUI: Forged chat-file link allows cross-user file read and deletion

Summary Open WebUI v0.9.5 lets an authenticated user attach arbitrary fileid values to their own chat message without checking whether they own or can read those files. If the attacker then shares that chat and grants themselves read access, hasaccesstofile treats the victim file as accessible...

PYSEC-2026-2698 Open WebUI: Jupyter code execution works despite `ENABLE_CODE_EXECUTION=false` — feature gate bypassed

Summary The /api/v1/utils/code/execute endpoint executes arbitrary Python code via Jupyter for any verified user, even when the admin has set ENABLECODEEXECUTION=false. The feature gate is not enforced on the API endpoint — the configuration says "disabled" but code still executes. Details The...

PYSEC-2026-2756 Open WebUI: Mass Assignment via FeedbackForm extra=allow Allows Feedback User ID Spoofing and Evaluation Data Manipulation

Mass Assignment in Feedback Creation Allows User ID Spoofing and Evaluation Data Manipulation Summary The POST /api/v1/evaluations/feedback endpoint in Open WebUI v0.9.2 is vulnerable to mass assignment via FeedbackForm, which uses modelconfig = ConfigDictextra='allow'. Due to an insecure...

Open WebUI Vulnerable to Unauthenticated RAG Configuration Disclosure

Vulnerability Type: Information Disclosure / Missing Authentication Severity: Medium Component: backend/openwebui/routers/retrieval.py — getstatus GET / Affected Endpoint: GET /api/v1/retrieval/ Affected Version: Open WebUI main branch — confirmed unpatched through v0.9.2 Authentication Required:...

PYSEC-2026-2715 Open WebUI has a Server-Side Request Forgery (SSRF) bypass in `validate_url`

Summary In the open-webui project, a parsing difference between the urlparse and requests libraries led to an SSRF bypass vulnerability. Details In the current project, URL validation is performed using the function validateurl. The current checking logic uses urlparse to parse the hostname part ...

PYSEC-2026-2705 Open WebUI has an IDOR vulnerability in the pin_channel_message API endpoint

Summary Pin/Unpin is a write operation modifies the message's ispinned , pinnedby, pinnedat fields, but in standard channels it only checks read permission, allowing users with read-only access to pin/unpin any message. Details...

PYSEC-2026-2714 Open WebUI: Low-privilege authenticated users can enumerate and stop global background tasks, causing system-wide chat disruption

Summary Any authenticated user with low privileges can enumerate active background tasks across the system and stop tasks belonging to other users via the GET /api/tasks and POST /api/tasks/stop/taskid methods. This allows a casual user to disrupt system-wide chat usage by continuously canceling...

Open WebUI Exposes System Prompt to Regular User [Non-Admin]

SummaryA regular user non-admin can view the system prompt of the model which is set by an admin. DetailsWhen a regular user non-admin logs into the application, a http://IP:8080/api/models? web request is initiated by the application and in response, it reveals the system prompt of available...

Open WebUI: shared-chat branch ignores access_type, allowing unauthorized file deletion

SummaryAny authenticated user can permanently delete files owned by other users via DELETE /api/v1/files/id when the target file is referenced in any shared chat. The hasaccesstofile authorization gate unconditionally grants access through its shared-chat branch. It checks neither the requesting...

PYSEC-2026-2706 Open WebUI Vulnerable to Unauthenticated RAG Configuration Disclosure

Vulnerability Type: Information Disclosure / Missing Authentication Severity: Medium Component: backend/openwebui/routers/retrieval.py — getstatus GET / Affected Endpoint: GET /api/v1/retrieval/ Affected Version: Open WebUI main branch — confirmed unpatched through v0.9.2 Authentication Required:...

PYSEC-2026-2767 Open WebUI has an IDOR vulnerability in the update_message_by_id API endpoint

Summary An IDOR vulnerability exists in the Channels feature of Open WebUI, allowing any channel member to modify messages sent by other members including administrators within the same channel. This vulnerability affects the latest version v0.8.12 of Open WebUI. Details In the updatemessagebyid...

PYSEC-2026-2755 Open WebUI has a SSRF Bypass via HTTP Redirect Following in Web-Fetch and Image-Load Endpoints (not addressed by CVE-2025-65958)

Server-Side Request Forgery SSRF Bypass via HTTP Redirect Following in Web-Fetch, Image-Load, and Chat-Completion Endpoints Summary The validateurl function in backend/openwebui/retrieval/web/utils.py only validates the initial URL submitted by the caller. The HTTP clients used downstream sync...