CVE-2026-8981

The Custom Block Builder WordPress plugin before 4.3.0 does not consistently check the unfiltered_html capability across all paths that write to its block template code fields, allowing administrators on multisite installations (or single-site installs with DISALLOW_UNFILTERED_HTML defined) to inject arbitrary JavaScript that executes for any visitor of pages embedding the affected block.

CVSS v3 3.5 LOW

3.5^/10

CVSS v3 : LOW

Vector :

Exploitability : 0.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://wpscan.com/vulnerability/9815b0e6-e411-4a5c-9c63-30bad21da698/

Configurations

No configuration.

History

23 Jul 2026, 08:10

Type	Values Removed	Values Added
Summary		(es) El plugin de WordPress Custom Block Builder anterior a la versión 4.3.0 no verifica de forma consistente la capacidad unfiltered_html en todas las rutas que escriben en sus campos de código de plantilla de bloque, permitiendo a los administradores en instalaciones multisitio (o instalaciones de sitio único con DISALLOW_UNFILTERED_HTML definido) inyectar JavaScript arbitrario que se ejecuta para cualquier visitante de las páginas que incrustan el bloque afectado.

09 Jun 2026, 11:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 3.5
CWE		CWE-79

09 Jun 2026, 06:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-09 06:16

Updated : 2026-07-23 08:10

NVD link : CVE-2026-8981

Mitre link : CVE-2026-8981

CVE.ORG link : CVE-2026-8981

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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