CVE-2026-56398
HIGHOpen WebUI - Stored Cross-Site Scripting via OAuth Picture Claim SVG Data URI
Title source: cnaDescription
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 (2)
Core 2
Core References
Vendor Advisory vendor-advisory
GitHub Security Advisory (GHSA-3wgj-c2hg-vm6q)
https://github.com/open-webui/open-webui/security/advisories/GHSA-3wgj-c2hg-vm6q
Third Party Advisory third-party-advisory
VulnCheck Advisory: Open WebUI - Stored Cross-Site Scripting via OAuth Picture Claim SVG Data URI
https://www.vulncheck.com/advisories/open-webui-stored-cross-site-scripting-via-oauth-picture-claim-svg-data-uri
Scores
CVSS v3
7.3
EPSS
0.0042
EPSS Percentile
34.3%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-20
Status
published
Products (3)
open-webui/open-webui
< 0.9.5
open-webui/open-webui
0.9.5
openwebui/open_webui
< 0.9.5
Published
Jul 15, 2026
Tracked Since
Jul 15, 2026