CVE-2026-123959
CriticalCVSS 9.1Summary
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.
Risk Assessment
A remote attacker could exploit the buffer overflow to disrupt device operation or potentially achieve code execution, threatening network confidentiality and integrity.
Recommendation
Update the TOTOLINK CA300-PoE firmware to the latest version or restrict access to the administrative interface to trusted addresses only.
Other vulnerabilities in TOTOLINK CA300-PoE
See all- CVE-2026-123961Critical
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.
- 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-2026-123958Critical
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 flaw has been discovered in TOTOLINK CA300-PoE 6.2c.884. The impacted element is the function setLanguageCfg of the file /cgi-bin/cstecgi.cgi. Performing a manipulation of the argument langType results in buffer overflow. The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS