{"schemaVersion":3,"id":"CVE-2026-56398","aliases":["GHSA-3wgj-c2hg-vm6q"],"status":"published","duplicateOf":null,"title":null,"description":"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 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