CVE-2026-4266

An Insecure Deserialization vulnerability in WatchGuard Fireware OS allows an attacker that has obtained write access to the local filesystem through another vulnerability to execute arbitrary code in the context of the portald user.This issue affects Fireware OS: 12.1 through 12.11.8 and 2025.1 through 2026.1.2. Note, this vulnerability does not affect Firebox platforms that do not support the Access Portal feature, including the T-15 and T-35.

CVSS

No CVSS.

References

Link	Resource
https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2026-00007

Configurations

No configuration.

History

17 Jun 2026, 10:56

Type	Values Removed	Values Added
Summary		(es) Una vulnerabilidad de deserialización insegura en WatchGuard Fireware OS permite a un atacante que ha obtenido acceso de escritura al sistema de archivos local a través de otra vulnerabilidad ejecutar código arbitrario en el contexto del usuario 'portald'. Este problema afecta a Fireware OS: 12.1 hasta 12.11.8 y 2025.1 hasta 2026.1.2. Tenga en cuenta que esta vulnerabilidad no afecta a las plataformas Firebox que no admiten la función Access Portal, incluyendo los T-15 y T-35.

30 Mar 2026, 13:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-30 13:16

Updated : 2026-06-17 10:56

NVD link : CVE-2026-4266

Mitre link : CVE-2026-4266

CVE.ORG link : CVE-2026-4266

JSON object : View

Products Affected

No product.

CWE

CWE-502

Deserialization of Untrusted Data

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