CVE-2026-56398: Improper Input Validation

Open WebUI before 0.9.5 contains a stored cross-site scripting vulnerability in the OAuth authentication flow where the picture claim URL MIME type is inferred from file extension rather than Content-Type header, allowing SVG files to bypass the profile image validator and be stored as data URIs...

CVE-2026-56400: Insufficient Session Expiration

open-webui before 0.3.14 contains a cross-origin resource sharing misconfiguration allowing arbitrary origins with alloworigins= and authenticated requests to the /api/v1/functions endpoint. Attackers can execute arbitrary code on the openwebui instance by crafting malicious cross-site requests...

The vulnerability of the _process_picture_url() function in the backend/open_webui/utils/oauth.py file of the Open WebUI AI-based web interface allows a attacker to perform an SSRF attack.

The vulnerability of the processpictureurl function in the backend/openwebui/utils/oauth.py file of the Open WebUI artificial intelligence-based web interface is related to insufficient validation of incoming requests. Exploiting this vulnerability could allow a malicious actor to perform an SSRF...

The vulnerability of the Open WebUI web interface, related to deficiencies in the authentication process, allows a perpetrator to gain access to read and modify data.

The vulnerability of the Open WebUI web interface is related to deficiencies in the authentication process. Exploiting this vulnerability can allow a malicious actor to gain access to and modify data...

The vulnerability of Ollama’s artificial intelligence-based web interface, Open WebUI, allows a hacker to gain unauthorized access to protected information.

The vulnerability of Ollama’s AI-based web interface, Open WebUI, is related to the lack of authentication during the processing of endpoints like /api/generate, /api/embed, /api/embeddings, and /api/show. Exploiting this vulnerability allows a malicious actor to gain unauthorized access to...

Open WebUI vulnerable to stored XSS via unescaped markdown token in MarkdownTokens.svelte leading to full account takeover and RCE via functions

SummaryA vulnerability in the way certain html tags in chat messages are rendered allows attackers to inject JavaScript code into a chat transcript. The JavaScript code will be executed in the user's browser every time that chat transcript is opened, allowing attackers to retrieve the user's acce...

Open WebUI vulnerable to Stored XSS via iFrame embeds in response messages

SummaryManually 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 on...

Open WebUI allows limited stored XSS vila uploaded html file

SummaryLow privileged users can upload HTML files which contain JavaScript code via the /api/v1/files/ backend endpoint. This endpoint returns a file id, which can be used to open the file in the browser and trigger the JavaScript code in the user's browser. Under the default settings, files...

PYSEC-2026-2769 Open WebUI vulnerable to Stored XSS via iFrame in citations model

Summary Manually modifying chat history allows setting the html property within document metadata. This causes the frontend to enter a code path that treats document contents as HTML, and render them in an iFrame when the citation is previewed. This allows stored XSS via a weaponised document...

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...

Open WebUI: RAG ACL Bypass in Milvus Multitenancy Mode

RAG ACL Bypass in Milvus Multitenancy Mode SummaryThis is a bypass of the fix for:- GHSA-h36f-rqpx-j5wx- CVE-2026-44560- "Unauthorized File and Knowledge Base Content Access via RAG Vector Search"Open WebUI added collection-level ACL checks, but the patch can still be bypassed when Milvus...

Open WebUI: Redirect-Bypass SSRF in OAuth `_process_picture_url` (incomplete-fix sibling of CVE-2026-45401)

Summarybackend/openwebui/utils/oauth.py::processpictureurl v0.9.5, lines 1435-1470 calls validateurlpictureurl on the initial URL only, then invokes aiohttp.ClientSession.getpictureurl, ... without allowredirects=False. aiohttp's default is allowredirects=True, maxredirects=10; the function does...

Open WebUI BOLA: `search_knowledge_files` Allows Unauthorized Knowledge Base File Enumeration

SummaryOpen 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...

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

SummaryThe 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 unauthorize...

Open WebUI: Sibling-Prefix Path Traversal via /cache/{path}

SummaryA path traversal vulnerability exists in open-webui's cache file serving endpoint that allows any authenticated user to read files from sibling directories outside the intended cache directory, by exploiting an incomplete startswith containment check that lacks a trailing path separator.Th...

Open WebUI: Stored XSS to Account Takeover via Model Profile Images

Stored XSS to Account Takeover via Model Profile Images in Open WebUIAffected: Open WebUI = 0.9.5Bypass of: GHSA-3wgj-c2hg-vm6q, GHSA-3856-3vxq-m6fc--- TL;DROpen WebUI patched SVG XSS in user profile images and webhook profile images but forgot to apply the same fix to model profile images. The...

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

SummaryOpen 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...

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-2026-2757 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...