CVE-2026-16771

In firmware versions 2.7.7 and earlier, the Arris BGW210‑700 gateway fails to enforce any server‑side authentication on its /cgi-bin/*.ha management endpoints, relying solely on client‑side CSS/JavaScript gating that can be bypassed by any HTTP client. This allows unauthenticated attackers on the LAN to read sensitive configuration data, modify persistent device settings, or trigger backend diagnostic operations. The issue appears systemic across the CGI handler chain.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://kb.cert.org/vuls/id/141367
https://www.kb.cert.org/vuls/id/141367

Configurations

No configuration.

History

23 Oct 2026, 23:10

Type	Values Removed	Values Added
Summary		(es) En las versiones de firmware 2.7.7 y anteriores, el gateway Arris BGW210?700 no aplica ninguna autenticación del lado del servidor en sus puntos finales de gestión /cgi-bin/*.ha, confiando únicamente en la restricción CSS/JavaScript del lado del cliente que puede ser eludida por cualquier cliente HTTP. Esto permite a atacantes no autenticados en la LAN leer datos de configuración sensibles, modificar configuraciones persistentes del dispositivo o activar operaciones de diagnóstico de backend. El problema parece sistémico en toda la cadena de gestores CGI.

Information

Published : 2026-07-28 19:17

Updated : 2026-10-23 23:10

NVD link : CVE-2026-16771

Mitre link : CVE-2026-16771

CVE.ORG link : CVE-2026-16771

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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