CVE-2026-2736

Reflected Cross-site Scripting (XSS) in Alkacon's OpenCms v18.0, which allows an attacker to execute JavaScript code in the victim's browser by sending the victim a malicious URL containing the ‘q’ parameter in ‘/search/index.html’. This vulnerability can be exploited to steal sensitive user information such as session cookies, or to perform actions while impersonating the user.

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://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-alkacons-opencms	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:alkacon:opencms:18.0.0:*:*:*:*:*:*:*

History

17 Jun 2026, 10:31

Type	Values Removed	Values Added
Summary		(es) Cross-site scripting (XSS) reflejado en OpenCms v18.0 de Alkacon, que permite a un atacante ejecutar código JavaScript en el navegador de la víctima enviando a la víctima una URL maliciosa que contiene el parámetro 'q' en '/search/index.html'. Esta vulnerabilidad puede ser explotada para robar información sensible del usuario como cookies de sesión, o para realizar acciones suplantando al usuario.

23 Feb 2026, 19:15

Type	Values Removed	Values Added
References	~~() https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-alkacons-opencms -~~	() https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-alkacons-opencms - Third Party Advisory
CPE		cpe:2.3:a:alkacon:opencms:18.0.0:::::::*
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.1
First Time		Alkacon opencms Alkacon

19 Feb 2026, 09:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-19 09:16

Updated : 2026-06-17 10:31

NVD link : CVE-2026-2736

Mitre link : CVE-2026-2736

CVE.ORG link : CVE-2026-2736

JSON object : View

Products Affected

alkacon

opencms

CWE

CWE-79

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

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