RCE in N/a

CVE-2026-36540

Netis AC1200 Router NC21 V4.0.1.4296 is vulnerable to unauthenticated command injection via the /cgi-bin/skk_set.cgi endpoint. The password and new_pwd_confirm POST parameters are passed directly to the underlying OS shell without sanitization. An attacker can inject arbitrary shell commands by wrapping them in backticks (`) and encoding them in base64. Because the endpoint requires no authentication, any device on the LAN can achieve full Remote Code Execution on the router's operating system with a single HTTP POST request.

Vulnerability class: Command Injection (OS Command Injection)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.

EPSS exploit prediction

EPSS: 0.013 (69.9th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 70th percentile — 69.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-36540: held from 0.013 to 0.013.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-36540?
CVE-2026-36540 is a high-severity vulnerability in N/a, classified under Command Injection. CVSS score: 7.3/10. Published 2026-05-27.
How severe is CVE-2026-36540?
High severity. CVSS v3 base score is 7.3 out of 10.