CVE-2026-36540 (GCVE-0-2026-36540)

Vulnerability from cvelistv5 – Published: 2026-05-27 00:00 – Updated: 2026-07-05 01:35
VLAI
Summary
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.
Severity
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-28 13:41 UTC
CWE
  • n/a
  • CWE-77 - Improper Neutralization of Special Elements used in a Command ('Command Injection')
Assigner
mitre CNA under the mitre root
CNA scorecard E 29/100 over 2324 records in the last 180 days details
References
Show details on NVD website
To clipboard 

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