CVE-2026-73628

Serendipity versions >= 2.3.5 and <= 2.6.0 contain a reflected cross-site scripting vulnerability in the search clean-URL route (/search/<term>). In include/functions_routing.inc.php serveSearch(), the sanitisation pipeline runs urldecode() after HTML-encoding, so a single URL-encoded HTML payload survives strip_tags() and htmlspecialchars() and is then decoded back into live HTML in the page. A crafted search link can execute arbitrary JavaScript in the victim's browser. Fixed in 2.6.1.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/s9y/Serendipity/security/advisories/GHSA-6c2x-mjmq-vx4q
https://www.vulncheck.com/advisories/serendipity-reflected-xss-via-search-clean-url-route
https://github.com/s9y/Serendipity/security/advisories/GHSA-6c2x-mjmq-vx4q

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-13 12:17

Updated : 2026-09-09 20:35

NVD link : CVE-2026-73628

Mitre link : CVE-2026-73628

CVE.ORG link : CVE-2026-73628

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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