CVE-2026-79670

Ech0 before 4.4.3 contains a stored cross-site scripting vulnerability in the file upload endpoint that validates Content-Type using only client-supplied headers without server-side inspection. Attackers with admin privileges can upload SVG or HTML files containing JavaScript that executes in the application origin when accessed by any user, enabling session hijacking and data exfiltration.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.7 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/lin-snow/Ech0/security/advisories/GHSA-69hx-63pv-f8f4
https://www.vulncheck.com/advisories/ech0-before-stored-xss-via-svg-upload
https://github.com/lin-snow/Ech0/security/advisories/GHSA-69hx-63pv-f8f4

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 12:16

Updated : 2026-08-31 20:52

NVD link : CVE-2026-79670

Mitre link : CVE-2026-79670

CVE.ORG link : CVE-2026-79670

JSON object : View

Products Affected

No product.

CWE

CWE-434

Unrestricted Upload of File with Dangerous Type

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