CVE-2026-9456
Published: 25 May 2026
Summary
CVE-2026-9456 is a high-severity Command Injection (CWE-77) vulnerability in Totolink A8000RU (inferred from references). Its CVSS base score is 8.9 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 22.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SC-7 (Boundary Protection) and SI-10 (Information Input Validation).
Deeper analysis
CVE-2026-9456 is an operating system command injection vulnerability in the Totolink A8000RU router running firmware version 7.1cu.643_b20200521. It is located in the setOpenVpnCfg function of the /cgi-bin/cstecgi.cgi file within the Web Management Interface component, where manipulation of the enabled argument permits injection of arbitrary OS commands. The issue is tracked under CWE-77 and CWE-78 and carries a CVSS 4.0 score of 8.9.
An unauthenticated attacker can exploit the flaw remotely over the network without user interaction or credentials by submitting specially crafted HTTP requests to the web interface, resulting in arbitrary command execution that affects confidentiality, integrity, and availability. A functional exploit for this vulnerability has been made publicly available.
The listed references include a GitHub repository with vulnerability details and proof-of-concept material, multiple Vuldb entries, and the vendor website, but contain no specific information on patches, firmware updates, or other mitigations. The EPSS score has remained flat at 0.0125 with no material rise since disclosure.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-31674
Vulnerability details
A vulnerability was found in Totolink A8000RU 7.1cu.643_b20200521. Impacted is the function setOpenVpnCfg of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. The manipulation of the argument enabled results in os command injection. The attack can be executed remotely.…
more
The exploit has been made public and could be used.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Remote OS command injection in web management interface directly enables T1190 (public-facing app exploit) and T1059.004 (Unix shell command execution).
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly requires validation and sanitization of the 'enabled' argument in setOpenVpnCfg before it reaches the OS, blocking the command injection vector in /cgi-bin/cstecgi.cgi.
Restricts remote network access to the web management interface, preventing unauthenticated attackers from reaching the vulnerable CGI endpoint.
Enforces authentication and access rules on the management interface so that the setOpenVpnCfg function cannot be invoked without valid credentials.