CVE-2026-76070 json
Netis NC63 V3.0.0.3327 Stack Buffer Overflow via Login Password Parameter
published 2026-08-24 2 mo ago modified 2026-10-12 27 d ago also EUVD-2026-64921
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.3%
- EPSS 1.3% chance of exploitation in 30 days, percentile 71%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- total
- Assessed
- 2 mo ago
Exploit prediction
1.34% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- ozcanpng.dev https://ozcanpng.dev/blog/cve-2026-76070-netis-nc63-login-stack-buffer-overflow/ referenced PoC, tagged "exploit" by a source, unverified
- github.com https://github.com/ozcanpng/CVE-2026-76070 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- Netis Systems NC63
Classification
- Weakness
-
- CWE-121 Stack-based Buffer Overflow
References
-
ozcanpng.dev
/blog/cve-2026-76070-netis-nc63-login-stack-buffer-overflow/
technical-description, exploit
-
github.com
/ozcanpng/CVE-2026-76070
technical-description, exploit
-
netis-systems.com
/products/NC63.html
product
-
vulncheck.com
/advisories/netis-nc63-stack-buffer-overflow-via-login-password-parameter
third-party-advisory
Sources
- CVE List CVE-2026-76070
- NVD CVE-2026-76070
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.