CVE-2026-5976
Published: 09 April 2026
Summary
CVE-2026-5976 is a high-severity Command Injection (CWE-77) vulnerability in Totolink A7100RU (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 24.3% 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 SI-10 (Information Input Validation) and AC-3 (Access Enforcement).
Deeper analysis
CVE-2026-5976 is an OS command injection vulnerability in the Totolink A7100RU router running firmware version 7.4cu.2313_b20191024. It resides in the setStorageCfg function within the /cgi-bin/cstecgi.cgi file of the CGI Handler component and is triggered by unsanitized input to the sambaEnabled argument, corresponding to CWE-77 and CWE-78.
The flaw can be exploited remotely by unauthenticated attackers over the network, allowing arbitrary operating system command execution with impacts to confidentiality, integrity, and availability. Public exploit code has been released, enabling straightforward weaponization against exposed devices.
The listed references include a GitHub repository containing a detailed proof-of-concept, multiple Vuldb entries, and the vendor homepage, but provide no information on patches or configuration mitigations. The associated EPSS score remains low at 0.0122 with a peak of 0.0125, indicating limited observed exploitation interest to date.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-21076
Vulnerability details
A security flaw has been discovered in Totolink A7100RU 7.4cu.2313_b20191024. This affects the function setStorageCfg of the file /cgi-bin/cstecgi.cgi of the component CGI Handler. Performing a manipulation of the argument sambaEnabled results in os command injection. It is possible to…
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initiate the attack remotely. The exploit has been released to the public and may be used for attacks.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Unauthenticated remote OS command injection via web CGI on a public-facing router directly enables T1190 (Exploit Public-Facing Application) and facilitates arbitrary Unix shell command execution (T1059.004).
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly requires validation and sanitization of untrusted input to the sambaEnabled parameter in setStorageCfg, blocking the OS command injection vector.
Enforces authentication and authorization checks before allowing any access to the CGI handler, preventing unauthenticated remote exploitation.
Restricts network traffic to the router's management interface and /cgi-bin/cstecgi.cgi endpoint from untrusted sources, blocking remote attack reachability.