CVE-2026-77218

PLANET GS-4210-16P2S V3 firmware before 3.441b260626 contains authenticated stack buffer overflow vulnerabilities in /cgi-bin/dispatcher.cgi. The web_login_first_post handler copies the usrPass POST parameter into a fixed-size stack buffer without length validation, the web_sys_enablePasswd_post handler copies the enbPass POST parameter into a fixed-size stack buffer without length validation, and the web_sys_localUser_post handler copies the usrName and usrPass POST parameters into fixed-size stack buffers without length validation. A remote authenticated attacker can send a crafted request to crash the CGI process or web management service, resulting in denial of service.

  • Published Aug 28, 2026
  • CVSS 6.9 medium
  • 0.6% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-77218 at the National Vulnerability Database