CVE-2026-51666
MediumCVSS 4.3Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
Incorrect access control in the setWizardCfg function of TOTOLINK T6 router (version 4.1.5cu.748_B20211015) allows unauthenticated attackers to reconfigure WAN, Wi-Fi, and device initialization state via a crafted POST request to /cgi-bin/cstecgi.cgi.
Risk Assessment
An attacker can change critical network settings, potentially leading to network outages, traffic interception, or full device compromise. This is a serious risk to network integrity and availability.
Recommendation
Update the router firmware to the latest version if available. Restrict access to the admin panel to trusted networks only.
Other vulnerabilities in TOTOLINK T6
See all- CVE-2026-51770Critical
Incorrect access control in the sendToMasterQosConfig function of TOTOLINK T6 (version 4.1.5cu.748_B20211015) allows unauthenticated attackers to forward attacker-controlled QoS settings to the master via sending a crafted MQTT message to the cs_broker component.
- CVE-2026-51769Critical
Incorrect access control in the remoteCloudUpdateCheck function of TOTOLINK T6 (version 4.1.5cu.748_B20211015) allows unauthenticated attackers to restart the cloud update check workflow via sending a crafted MQTT message to the cs_broker component.
- CVE-2026-51767Critical
Incorrect access control in the recvClearPairCfg function of TOTOLINK T6 (version 4.1.5cu.748_B20211015) allows unauthenticated attackers to reset pairing state and reboot the device via sending a crafted MQTT message to the cs_broker component.
- CVE-2026-51765Critical
Incorrect access control in the recvIndirectMeshInfo function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to insert or replace mesh neighbor records via sending a crafted MQTT message to the cs_broker component.
- CVE-2026-51764Critical
Incorrect access control in the recvSlaveCloudCheckStatus function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to overwrite cloud-result tracking files via sending a crafted MQTT message to the cs_broker component.
- CVE-2026-51763Critical
Incorrect access control in the freeStaClient function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to forcibly disconnect wireless clients via sending a crafted MQTT message to the cs_broker component.
- CVE-2026-51762Critical
Incorrect access control in the meshInfoKick function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to kick or clean stale mesh information/state and trigger regeneration of mesh metadata via sending a crafted MQTT message to the cs_broker component.
- CVE-2026-51760Critical
Incorrect access control in the informSyncUpgfw function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to mass-trigger firmware update activity across mesh slaves via sending a crafted MQTT message to the cs_broker component.
- CVE-2026-51757Critical
Incorrect access control in the meshSlaveUpdate function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to start a firmware download or flash workflow on the slave device via sending a crafted MQTT message to the cs_broker component.
- CVE-2026-51754Critical
Incorrect access control in the updateSlaveIpList function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to overwrite the slave IP inventory state via sending a crafted MQTT message to the cs_broker component.
Original NVD description (English source)
Incorrect access control in the setWizardCfg function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to reconfigure WAN, Wi-Fi, and device initialization state via sending a crafted POST request to /cgi-bin/cstecgi.cgi.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS