Publicly Exploitable Command Injection Flaws Disclosed in Totolink A3300R Router
Two high-severity command injection vulnerabilities have been disclosed in the Totolink A3300R router, both affecting firmware version 17.0.0cu.557_b20221024 and exposing the device to remote code execution through /cgi-bin/cstecgi.cgi. The flaws are tracked as CVE-2026-5104 and CVE-2026-5101. CVE-2026-5104 affects the setStaticRoute function, where manipulation of the ip argument can trigger command injection, while CVE-2026-5101 affects the setLanCfg function in the Parameter Handler component through the lanIp argument.
Public exploit material has been disclosed for both issues, according to VulDB and referenced advisory material, raising the risk of active abuse against exposed devices. NVD subsequently added initial analysis for the CVEs, assigning higher CVSS v3.1 severity assessments than the original CNA submissions and mapping the weaknesses to CWE-77, CWE-74, and CWE-78. The disclosures indicate that attackers could remotely inject operating system commands via crafted requests, making patching, exposure reduction, and monitoring of internet-facing Totolink A3300R systems urgent priorities.
Timeline
Apr 23, 2026
CVE-2026-31181 disclosed for Totolink A3300R command injection flaw
A CVE record was published for a remotely exploitable command injection vulnerability in /cgi-bin/cstecgi.cgi on Totolink A3300R firmware v17.0.0cu.557_B20221024. The flaw involves the stunServerAddr parameter, and the record was updated the same day with critical CVSS v3.1 scoring, CWE-78 classification, and a GitHub reference documenting the issue.
Apr 23, 2026
CVE-2026-31178 disclosed for Totolink A3300R command injection flaw
A CVE record was published for a remotely exploitable command injection vulnerability in /cgi-bin/cstecgi.cgi on Totolink A3300R firmware v17.0.0cu.557_B20221024. The flaw involves the stunMaxAlive parameter, and the record was updated the same day with critical CVSS v3.1 scoring, CWE-78 classification, and a GitHub reference containing technical details.
Apr 23, 2026
CVE-2026-31177 disclosed for Totolink A3300R command injection flaw
A CVE record was published for a remotely exploitable command injection vulnerability in /cgi-bin/cstecgi.cgi on Totolink A3300R firmware v17.0.0cu.557_B20221024. The flaw involves the stunMinAlive parameter, and the record was updated the same day with critical CVSS v3.1 scoring, CWE-78 classification, and a GitHub reference containing technical details.
Apr 23, 2026
CVE-2026-31175 disclosed for Totolink A3300R command injection flaw
A CVE record was published for a remotely exploitable command injection vulnerability in /cgi-bin/cstecgi.cgi on Totolink A3300R firmware v17.0.0cu.557_B20221024. The flaw involves the stunEnable parameter, and the record was updated the same day with a critical CVSS v3.1 vector, CWE-77 classification, and a GitHub reference for vulnerability details and proof-of-concept information.
Mar 30, 2026
CVE-2026-5103 disclosed for Totolink A3300R command injection flaw
A CVE record was published for a remotely exploitable command injection vulnerability in the setUPnPCfg function of /cgi-bin/cstecgi.cgi on Totolink A3300R firmware 17.0.0cu.557_b20221024. The flaw involves manipulation of the enable argument, and the reference notes public exploit information was available and later NVD analysis increased the severity rating.
Mar 30, 2026
CVE-2026-5105 disclosed for Totolink A3300R command injection flaw
A CVE record was published for a command injection vulnerability in the setVpnPassCfg function of /cgi-bin/cstecgi.cgi on Totolink A3300R firmware 17.0.0cu.557_b20221024. The flaw involves the pptpPassThru argument, is exploitable remotely, and public exploit material was referenced by VulDB and GitHub.
Mar 30, 2026
CVE-2026-5102 disclosed for Totolink A3300R command injection flaw
A CVE record was published for a remotely exploitable command injection vulnerability in the setSmartQosCfg function of /cgi-bin/cstecgi.cgi on Totolink A3300R firmware 17.0.0cu.557_b20221024. The flaw involves the qos_up_bw argument, and the reference notes public exploit information was available the same day.
Mar 30, 2026
NVD publishes initial analysis for Totolink A3300R CVEs
NVD added its initial analysis for the Totolink A3300R command injection vulnerabilities, including CVE-2026-5101 and CVE-2026-5104, on March 30, 2026. The enrichment included higher CVSS v3.1 scoring and additional weakness or affected-product mappings.
Mar 29, 2026
Public exploit disclosed for CVE-2026-5101 and CVE-2026-5104
Public exploit material and advisory information for two Totolink A3300R command injection flaws were disclosed via sources referenced by VulDB and GitHub. The disclosures covered the setLanCfg and setStaticRoute functions in /cgi-bin/cstecgi.cgi and indicated the issues may be used in attacks.
Mar 29, 2026
CVE-2026-5101 received for Totolink A3300R command injection flaw
A CVE record was created for a command injection vulnerability in the setLanCfg function of /cgi-bin/cstecgi.cgi on Totolink A3300R firmware 17.0.0cu.557_b20221024. The flaw involves manipulation of the lanIp argument and can be exploited remotely.
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