CVE-2026-56398 (GCVE-0-2026-56398)
Vulnerability from cvelistv5
Published
2026-07-15 11:25
Modified
2026-07-15 13:25
Severity ?
8.5 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
7.3 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
CWE
  • CWE-20 - Improper Input Validation
Summary
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.
References
Impacted products
Vendor Product Version
open-webui open-webui Version: 0   ≤
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