Multiple exploitable stack-based buffer overflow vulnerabilities exist in the boa formIpv6Setup dhcp_dns functionality of X2000R (version(s):… (CVE-2026-42025)

The TOTOLINK X2000R router firmware version TOTOLINK-X2000R-Gh-V1.0.0-B20250421.1327 contains multiple exploitable stack-based buffer overflow vulnerabilities within the boa web server's formIpv6Setup dhcp_dns functionality. Specifically, the dhcp_dns1 parameter in an authenticated HTTP request can be manipulated to cause a buffer overflow, leading to arbitrary code execution. The vulnerabilities are identified under CVE-2026-42025 and have a CVSS 3.1 score of 9.1, indicating critical severity. There is no information about available patches or vendor advisories, and no known exploits in the wild have been reported.

Successful exploitation of these vulnerabilities allows an authenticated attacker to execute arbitrary code on the affected device, potentially leading to full compromise of the router. This can impact confidentiality, integrity, and availability of the device and the network it serves.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to the device's management interface to trusted users only and monitor for suspicious authenticated HTTP requests targeting the dhcp_dns1 parameter.