CVE-2026-56398
HighCVSS 7.3Exploitation Probability (EPSS)
Low risk26th percentile - higher than 26% of all known CVEs
Summary
Open WebUI before version 0.9.5 contains a stored cross-site scripting vulnerability in the OAuth authentication flow. The MIME type of the profile picture URL is inferred from the file extension rather than the Content-Type header, allowing SVG files to bypass the profile image validator and be stored as data URIs. Authenticated users visiting the profile image endpoint receive attacker-controlled SVG content, enabling script execution in the same origin to steal authentication tokens and achieve account takeover.
Risk Assessment
The risk for the organization includes the potential theft of session tokens and account takeover, which can lead to unauthorized access to sensitive data and compromise system integrity.
Recommendation
It is recommended to immediately upgrade Open WebUI to version 0.9.5 or later, which fixes this vulnerability. Additionally, consider implementing security headers (e.g., Content-Security-Policy) for profile image endpoints.
Other vulnerabilities in Open WebUI
See all- CVE-2026-45350High
In Open WebUI prior to version 0.8.6, there is a vulnerability in the chat completion API that allows attackers to bypass tool restrictions, potentially enabling unauthorized actions or access.
- CVE-2026-45338High
In Open WebUI prior to version 0.9.0, a Server-Side Request Forgery (SSRF) vulnerability exists in the _process_picture_url() function, allowing an attacker to force the server to make HTTP requests to internal resources.
- CVE-2026-45315High
Open WebUI prior to version 0.9.3 has a vulnerability that allows audio files with HTML extensions to be uploaded, potentially leading to the execution of malicious code in users' browsers. A user with the appropriate permissions can trick others into opening a malicious link.
- CVE-2026-45303High
Open WebUI is a self-hosted artificial intelligence platform that prior to version 0.6.5 allowed for script injection and execution through the HTML rendering view. The chat content was embedded in an iFrame with sandbox restrictions that were largely ineffective.
- CVE-2026-45301High
Open WebUI is a self-hosted artificial intelligence platform that prior to version 0.3.16 had a missing permission check in files related to API endpoints. This allowed any authenticated user to list, access, and delete every file uploaded by other users.
- CVE-2026-44570High
In Open WebUI prior to version 0.6.19, there were inconsistencies in authorization controls surrounding the memories API, allowing standard users to delete, restore, and view the contents of other users' memories.
- CVE-2026-44569High
In Open WebUI prior to version 0.6.19, there is an IDOR vulnerability in the channels message management system that allows authenticated users to modify or delete any message within channels they have access to. The issue arises from a lack of message ownership validation in the message update and delete endpoints.
- CVE-2026-44567High
Open WebUI is a self-hosted artificial intelligence platform that prior to version 0.1.124 did not properly validate whether a user has an authorized role. By default, when new user sign-ups are enabled, the user role is set to 'pending', requiring administrator intervention to assign the appropriate role.
- CVE-2026-44566High
Open WebUI is an artificial intelligence platform that prior to version 0.1.124 did not validate or sanitize file names uploaded by users. This allows users to upload files with names containing dot-segments, enabling traversal out of the intended upload directory.
- CVE-2026-44565High
Open WebUI is a self-hosted artificial intelligence platform that prior to version 0.6.10 did not validate or sanitize file names when uploading audio files. This allows users to upload files with names containing dot-segments, enabling traversal out of the intended uploads directory.
Original NVD description (English source)
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. Authenticated users who visit the profile image endpoint receive attacker-controlled SVG content with inline disposition and no default security headers, enabling script execution in the same origin to steal authentication tokens and achieve account takeover.

