CVE-2026-56398

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.

CVSS v3 7.3 HIGH

7.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.1 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/open-webui/open-webui/security/advisories/GHSA-3wgj-c2hg-vm6q	Exploit Vendor Advisory
https://www.vulncheck.com/advisories/open-webui-stored-cross-site-scripting-via-oauth-picture-claim-svg-data-uri	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-15 12:18

Updated : 2026-07-16 20:03

NVD link : CVE-2026-56398

Mitre link : CVE-2026-56398

CVE.ORG link : CVE-2026-56398

JSON object : View

Products Affected

openwebui

open_webui

CWE

CWE-20

Improper Input Validation

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