Description
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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Netis Systems | NC63 | ≤ 3.0.0.3327 | — |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 1 repository
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ozcanpng/CVE-2026-76071 ★ 1 · Aug 19, 2026
Original research and PoC for a pre-auth stack buffer overflow via unbounded sscanf scanset in the Netis NC63 ipFilterList handler
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
References
- Researcher Blog technical-description exploit
- Researcher GitHub Repo technical-description exploit
- Product Page product
- https://www.vulncheck.com/advisories/netis-nc63-stack-buffer-overflow-via-desthost-parameter third-party-advisory