CVE-2025-7673

A buffer overflow vulnerability in the URL parser of the zhttpd web server in Zyxel VMG8825-T50K firmware versions prior to V5.50(ABOM.5)C0 could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and potentially execute arbitrary code by sending a specially crafted HTTP request. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

CVE-2025-7673 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

CVE-2025-7673 affects products from zyxel, specifically: emg3525-t50b, emg3525-t50b_firmware, emg5523-t50b, emg5523-t50b_firmware, emg5723-t50k, emg5723-t50k_firmware, emg6726-b10a, emg6726-b10a_firmware, ex3510-b0, ex3510-b0_firmware, ex5510-b0, ex5510-b0_firmware, vmg1312-t20b, vmg1312-t20b_firmware, vmg3625-t50b, vmg3625-t50b_firmware, vmg3925-b10b, vmg3925-b10b_firmware, vmg3925-b10c, vmg3925-b10c_firmware, vmg3927-b50a, vmg3927-b50a_firmware, vmg3927-b50b, vmg3927-b50b_firmware, vmg3927-b60a, vmg3927-b60a_firmware, vmg3927-t50k, vmg3927-t50k_firmware, vmg4005-b50b, vmg4005-b50b_firmware, vmg4927-b50a, vmg4927-b50a_firmware, vmg8623-t50b, vmg8623-t50b_firmware, vmg8825-b50a, vmg8825-b50a_firmware, vmg8825-b60a, vmg8825-b60a_firmware, vmg8825-bx0b, vmg8825-bx0b_firmware, vmg8825-t50k, vmg8825-t50k_firmware, vmg8924-b10d, vmg8924-b10d_firmware, xmg3927-b50a, xmg3927-b50a_firmware, xmg8825-b50a, xmg8825-b50a_firmware. Check the affected products table above for specific version ranges.

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.