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

SummaryAny 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...

PYSEC-2026-2727 Open WebUI missing authorization check at the model update function - models from other users can be updated

Summary A user can modify another user's model even if its visibility is set to Private. The finding resulted from a penetration test for a customer. It is suspected that the root cause of the issue lies within the core of Open WebUI, which is why it is being reported as a security issue here...

PYSEC-2026-2726 Open WebUI has Broken Access Control for Completions API

Summary Any user X can continue the conversation of any other user Y, as long as the Chat ID of Y is known. User X does not even need to be an admin to do so. Details A user just needs to use the API endpoint: /api/chat/completions with their own API key generated in OWUI and the Chat ID of anoth...

PYSEC-2026-2744 Open WebUI has stored XSS in Excel file preview

Summary Excel file attachments are previewed in an unsafe way. A crafted XLSX file payload can be used to cause the sheetjs function sheettohtml to embed an XSS payload into the generated HTML. This is subsequently added to the DOM unsanitized via @html causing the payload to trigger. Details The...

Open WebUI: Deactivated Channel Members Retain Full Access to Group/DM Channels

Deactivated Channel Members Retain Full Access to Group/DM Channels Affected ComponentChannel membership authorization check:- backend/openwebui/models/channels.py lines 663-673, isuserchannelmember- Used at 15 locations in backend/openwebui/routers/channels.py Affected VersionsCurrent main branc...

pyLoad has Stale Session Privilege After Role/Permission Change (Privilege Revocation Bypass)

SummarypyLoad caches role and permission in the session at login and continues to authorize requests using these cached values, even after an admin changes the user's role/permissions in the database.As a result, an already logged-in user can keep old revoked privileges until logout/session expir...

Open WebUI's process_files_batch() endpoint missing ownership check, allows unauthorized file overwrite

SummaryAny authenticated user can overwrite any file's content by ID through the POST /api/v1/retrieval/process/files/batch endpoint. The endpoint performs no ownership check, so a regular user with read access to a shared knowledge base can obtain file UUIDs via GET /api/v1/knowledge/id/files an...

PYSEC-2026-2979 Pydantic AI has Stored XSS via Path Traversal in Web UI CDN URL

Summary A Path Traversal vulnerability in the Pydantic AI web UI allows an attacker to serve arbitrary JavaScript in the context of the application by crafting a malicious URL. If a victim clicks the link or visits it via an iframe, attacker-controlled code executes in their browser, enabling the...

Pydantic AI has Stored XSS via Path Traversal in Web UI CDN URL

SummaryA Path Traversal vulnerability in the Pydantic AI web UI allows an attacker to serve arbitrary JavaScript in the context of the application by crafting a malicious URL. If a victim clicks the link or visits it via an iframe, attacker-controlled code executes in their browser, enabling thef...

PT-2026-59608

Summary A Path Traversal vulnerability in the Pydantic AI web UI allows an attacker to serve arbitrary JavaScript in the context of the application by crafting a malicious URL. If a victim clicks the link or visits it via an iframe, attacker-controlled code executes in their browser, enabling the...

PT-2026-59610

Summary A Path Traversal vulnerability in the Pydantic AI web UI allows an attacker to serve arbitrary JavaScript in the context of the application by crafting a malicious URL. If a victim clicks the link or visits it via an iframe, attacker-controlled code executes in their browser, enabling the...

PT-2026-59368

Summary Any user X can continue the conversation of any other user Y, as long as the Chat ID of Y is known. User X does not even need to be an admin to do so. Details A user just needs to use the API endpoint: /api/chat/completions with their own API key generated in OWUI and the Chat ID of anoth...

PT-2026-59407

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 update message by ...

EUVD-2026-42722

Hermes WebUI before 0.51.788 contains an unauthenticated remote code execution vulnerability that allows remote attackers to execute arbitrary shell commands by accessing the embedded terminal API endpoints without credentials. Attackers can create a session, attach a PTY shell, and write arbitra...

CVE-2026-14480: External Control of File Name or Path

OpenPLC Runtime v3 contains an authenticated arbitrary file write vulnerability in the legacy web UI program‑upload workflow. The application stores an attacker‑supplied filename progfile directly into the Programs.File database field and later uses this value as the destination path for an...

CVE-2026-59223

Open WebUI vulnerability CVE-2026-59223 affects the WEB_FETCH_FILTER_LIST logic prior to 0.10.0, allowing path-based blocklist bypasses (e.g., !internal.example.com in a URL path) and misalignment with hostname policy for sibling-domain matches. The issue is fixed in version 0.10.0. Impact is a p...

CVE-2026-59227

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.8.11 before 0.10.0, POST /api/v1/images/edit required only a verified account and did not enforce the global image-edit switch or the per-user image-generation permission, allowing a non-admin user to...

CVE-2026-5922 Poly Voice – Potential Unauthorized Modification of WebUI using XSS Attack

The IP phone might use malicious input stored in configuration parameters and render it as content for the WebUI’s webpage...

GHSA-JGX9-JR5X-MVPV Open WebUI has Blind Server Side Request Forgery in its Image Edit Functionality

Summary There is a blind server side request forgery in the functionality that allows editing an image via a prompt. The affected function will perform a GET request on the URL provided by the user. There is no restriction on the domain of the provided URL allowing the local address space to be...

GHSA-VJM7-M4XH-7WRC Open WebUI vulnerable to Stored XSS via iFrame embeds in response messages

Summary Manually modifying chat history allows setting the embeds property on a response message, the content of which is loaded into an iFrame with a sandbox that has allow-scripts and allow-same-origin set, ignoring the "iframe Sandbox Allow Same Origin" configuration. This enables stored XSS o...