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CVE-2026-56398

Open WebUI - Stored Cross-Site Scripting via OAuth Picture Claim SVG Data URI

Published: Jul 15, 2026Updated: Jul 16, 2026 Sources: CVE List NVDCWE-20
7.3HIGH
NVD MITRE
EPSS Score
0.4%
Top 65.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

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 takeover.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:RS:UC:HI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

CWE-20

Affected Products

open-webui
oss-projectaka open-webui/open-webui
open-webuiOn-premWeb App
AI / ML / ai-agent-tooling
openwebui
oss-projectaka open webui
open webuiOn-premWeb App
AI / ML / ai-agent-tooling

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Initial Access
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References

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

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