CVE-2026-76071

Netis NC63 firmware through V3.0.0.3327 contains a stack-based buffer overflow vulnerability that allows unauthenticated remote attackers to overwrite saved stack state by supplying an oversized destHost parameter to the ipFilterList=mod action in netis.cgi. Attackers can exploit widthless sscanf conversions that copy user-supplied input into fixed-size stack buffers before authentication is verified, achieving remote code execution as root due to the Boa web server executing the CGI environment with root privileges.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector 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://github.com/ozcanpng/CVE-2026-76071
https://ozcanpng.dev/blog/cve-2026-76071-netis-nc63-ipfilter-stack-buffer-overflow/
https://www.netis-systems.com/products/NC63.html
https://www.vulncheck.com/advisories/netis-nc63-stack-buffer-overflow-via-desthost-parameter

Configurations

No configuration.

History

12 Oct 2026, 15:10

Type	Values Removed	Values Added
Summary		(es) El firmware de Netis NC63 hasta V3.0.0.3327 contiene una vulnerabilidad de desbordamiento de búfer basado en pila que permite a atacantes remotos no autenticados sobrescribir el estado de pila guardado al proporcionar un parámetro destHost de tamaño excesivo a la acción ipFilterList=mod en netis.cgi. Los atacantes pueden explotar conversiones sscanf sin ancho que copian la entrada proporcionada por el usuario en búferes de pila de tamaño fijo antes de que se verifique la autenticación, logrando la ejecución remota de código como root debido a que el servidor web Boa ejecuta el entorno CGI con privilegios de root.

Information

Published : 2026-08-24 16:17

Updated : 2026-10-12 15:10

NVD link : CVE-2026-76071

Mitre link : CVE-2026-76071

CVE.ORG link : CVE-2026-76071

JSON object : View

Products Affected

No product.

CWE

CWE-121

Stack-based Buffer Overflow

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