CVE-2026-5176
Published: 31 March 2026
Summary
CVE-2026-5176 is a high-severity Injection (CWE-74) vulnerability in Totolink A3300R Firmware. Its CVSS base score is 7.3 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 15.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SC-14 (Public Access Protections) and SI-10 (Information Input Validation).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly prevents command injection vulnerability by validating arguments provided to the setSyslogCfg function in cstecgi.cgi.
Requires timely identification, reporting, and correction of the specific command injection flaw through patching or firmware updates.
Enforces authorizations and security requirements on the publicly accessible vulnerable CGI endpoint to block unauthenticated remote exploitation.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The vulnerability is a command injection in a public-facing CGI web interface on a router, enabling unauthenticated remote exploitation (T1190) for arbitrary command execution akin to network device CLI abuse (T1059.008).
NVD Description
A security flaw has been discovered in Totolink A3300R 17.0.0cu.557_b20221024. Affected is the function setSyslogCfg of the file /cgi-bin/cstecgi.cgi. Performing a manipulation of the argument provided results in command injection. The attack may be initiated remotely. The exploit has been…
more
released to the public and may be used for attacks.
Deeper analysisAI
CVE-2026-5176 is a command injection vulnerability affecting the Totolink A3300R router on firmware version 17.0.0cu.557_b20221024. The flaw resides in the setSyslogCfg function within the /cgi-bin/cstecgi.cgi file, where manipulation of a provided argument enables arbitrary command execution.
The vulnerability can be exploited remotely by unauthenticated attackers with low complexity and no user interaction required, per its CVSS 3.1 vector AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L, yielding a base score of 7.3. Successful exploitation grants limited impacts on confidentiality, integrity, and availability, mapped to CWEs-74 and CWE-77.
Advisories and references, including VulDB entries at https://vuldb.com/vuln/354244 and https://vuldb.com/submit/779145, detail the issue, while a public exploit is available at https://github.com/LvHongW/Vuln-of-totolink_A3300R/tree/main/A3300R_rtLogServer_cmd_inject. The manufacturer's site at https://www.totolink.net/ provides further context.
The exploit has been released publicly and may be used for attacks, as noted in the CVE description published on 2026-03-31.
Details
- CWE(s)