Incorrect default permissions in ZyXEL Communications Corp. products - CVE-2025-0890

Vulnerability identifier: #VU103597

CSH Severity: High

CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2025-0890

CWE-ID: CWE-276

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to escalate privileges on the system.

The vulnerability exists due to insecure default credentials for the Telnet function. A remote attacker can log in to the management interface on the target device.

VMG1312-B10A
VMG1312-B10B
VMG1312-B10E
VMG3312-B10A
VMG3313-B10A
VMG3926-B10B
VMG4325-B10A
VMG4380-B10A
VMG8324-B10A
VMG8924-B10A
SBG3300
SBG3500

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

• https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-command-injection-and-insecure-default-credentials-vulnerabilities-in-certain-legacy-dsl-cpe-02-04-2025

• Incorrect default permissions in Zyxel CPE series devices