CVE-2026-76070

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 submitting an oversized Base64-encoded password to the login handler in /bin/netis.cgi. Attackers can exploit the custom Base64 decoder's lack of output length validation against the fixed-size stack buffer to achieve remote code execution with root privileges, as the Boa web server executes the CGI environment as root.

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-2026-76070
https://ozcanpng.dev/blog/cve-2026-76070-netis-nc63-login-stack-buffer-overflow/
https://www.netis-systems.com/products/NC63.html
https://www.vulncheck.com/advisories/netis-nc63-stack-buffer-overflow-via-login-password-parameter

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-24 16:17

Updated : 2026-08-24 19:16

NVD link : CVE-2026-76070

Mitre link : CVE-2026-76070

CVE.ORG link : CVE-2026-76070

JSON object : View

Products Affected

No product.

CWE

CWE-121

Stack-based Buffer Overflow

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