CVE-2026-5997
Published: 10 April 2026
Summary
CVE-2026-5997 is a critical-severity Command Injection (CWE-77) vulnerability in Totolink A7100RU (inferred from references). Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 20.7% 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 IA-8 (Identification and Authentication (Non-organizational Users)) and SI-10 (Information Input Validation).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly prevents OS command injection by requiring validation of untrusted inputs like the admpass argument in the setLoginPasswordCfg CGI function.
Mandates identification, reporting, and correction of the specific command injection flaw in /cgi-bin/cstecgi.cgi to eliminate the vulnerability.
Blocks unauthenticated remote exploitation of the vulnerable CGI handler by enforcing identification and authentication for non-organizational users accessing the system.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The vulnerability is a remote unauthenticated OS command injection in a public-facing web CGI interface on a router, directly enabling T1190 (Exploit Public-Facing Application) and facilitating arbitrary command execution matching T1059.008 (Network Device CLI).
NVD Description
A vulnerability was detected in Totolink A7100RU 7.4cu.2313_b20191024. The impacted element is the function setLoginPasswordCfg of the file /cgi-bin/cstecgi.cgi of the component CGI Handler. The manipulation of the argument admpass results in os command injection. It is possible to launch…
more
the attack remotely. The exploit is now public and may be used.
Deeper analysisAI
CVE-2026-5997 is an OS command injection vulnerability in the Totolink A7100RU router running firmware version 7.4cu.2313_b20191024. The flaw affects the setLoginPasswordCfg function in the /cgi-bin/cstecgi.cgi file of the CGI Handler component, where manipulation of the admpass argument enables command injection. Published on 2026-04-10, it is associated with CWE-77 and CWE-78.
The vulnerability is exploitable remotely by unauthenticated attackers with low complexity and no user interaction required, earning a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H). Successful exploitation grants high impacts on confidentiality, integrity, and availability, allowing attackers to execute arbitrary OS commands and potentially fully compromise the device.
Advisories reference a public exploit in a GitHub repository at https://github.com/Litengzheng/vuldb_new/blob/main/A7100RU/vul_169/README.md, along with VulDB entries at https://vuldb.com/vuln/356551 and related pages. The Totolink website at https://www.totolink.net/ is listed, but no specific patches or mitigations are detailed in the provided references.
Details
- CWE(s)