CVE-2026-79663

Ech0 before 4.7.3 contains a stored cross-site scripting vulnerability in the public RSS feed where tag names and markdown content are rendered without HTML escaping. Attackers with admin privileges can inject malicious tag names or raw HTML in echo content that executes as JavaScript in RSS readers that render HTML-type summaries, affecting anonymous subscribers and other users.

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-3v85-fqvh-7rxf
https://www.vulncheck.com/advisories/ech0-before-stored-xss-via-rss-feed-tag-names

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-25 12:16

Updated : 2026-08-31 20:38

NVD link : CVE-2026-79663

Mitre link : CVE-2026-79663

CVE.ORG link : CVE-2026-79663

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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