CVE-2026-123961
CriticalCVSS 9.9Summary
A vulnerability was detected in TOTOLINK CA300-PoE version 6.2c.884 affecting the setWiFiBasicConfig function in /cgi-bin/cstecgi.cgi. Manipulation of the KeyStr argument leads to a buffer overflow. The attack can be initiated remotely and a public exploit is available.
Risk Assessment
A remote attacker could exploit the buffer overflow to destabilize the device or potentially execute code. Since the exploit is public, the risk is high for exposed devices.
Recommendation
Update the TOTOLINK CA300-PoE firmware to a non-vulnerable version or restrict access to the management interface. Until patched, consider isolating the device from untrusted networks.
Other vulnerabilities in TOTOLINK CA300-PoE
See all- CVE-2026-123960Critical
In TOTOLINK CA300-PoE version 6.2c.884, the setWanConfig function in /cgi-bin/cstecgi.cgi improperly handles the pppoeUser/priDns/secDns arguments, leading to a buffer overflow. The vulnerability can be exploited remotely, and a public exploit is already available.
- CVE-2026-123959Critical
In TOTOLINK CA300-PoE version 6.2c.884, the setLanguageCfg function in /cgi-bin/cstecgi.cgi improperly processes the langType argument, resulting in a buffer overflow. The attack can be initiated remotely, and the exploit has been publicly released.
- CVE-2026-123958Critical
In TOTOLINK CA300-PoE version 6.2c.884, the setLanConfig function in /cgi-bin/cstecgi.cgi mishandles the lanDns/lanSecDns/langType arguments, leading to a buffer overflow. The vulnerability can be exploited remotely, and a public exploit is already available.
- CVE-2026-123957Critical
In TOTOLINK CA300-PoE version 6.2c.884, the setIpQosRules function in /cgi-bin/cstecgi.cgi mishandles the ipStart argument, leading to a buffer overflow. The vulnerability can be exploited remotely, and the exploit has been publicly disclosed.
Original NVD description (English source)
A security vulnerability has been detected in TOTOLINK CA300-PoE 6.2c.884. This impacts the function setWiFiBasicConfig of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument KeyStr leads to buffer overflow. The attack may be initiated remotely. The exploit has been disclosed publicly and may be used.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

