Critical ASUS DSL Router Flaw (CVE-2025-59367, CVSS 9.3) Allows Unauthenticated Remote Access

Ddos November 14, 2025 2 minutes read

ASUS has released an urgent security advisory addressing a critical authentication bypass vulnerability affecting several models in its DSL Series Router lineup. The flaw, tracked as CVE-2025-59367 with a CVSSv4 score of 9.3, could allow remote threat actors to access affected systems without valid credentials, posing a severe risk to home users and small businesses relying on these devices.

According to ASUS, “A security vulnerability has been identified in certain ASUS DSL Series Router… An authentication bypass vulnerability… may allow remote attackers to gain unauthorized access into the affected system.”

Authentication bypass flaws are among the most dangerous vulnerabilities for networking devices because attackers can:

Log in without credentials
Modify router settings
Hijack internet traffic
Install persistent malware
Join the device into botnets
Intercept sensitive communications

Given the widespread use of ASUS DSL routers in homes and SMEs, exploitation could result in large-scale compromise if users fail to update promptly.

ASUS has released a new firmware update that fully addresses the vulnerability for supported models.

The update is available for:

Model	Fixed Firmware Version
DSL-AC51	1.1.2.3_1010
DSL-N16	1.1.2.3_1010
DSL-AC750	1.1.2.3_1010

ASUS strongly advises users to update immediately. Firmware downloads are available on each device’s product page or through the ASUS support portal.

Some older DSL router models have reached End-of-Life (EOL) and cannot receive the new security update. For these unsupported devices, ASUS recommends strict security hardening. ASUS instructs users of EOL devices to disable all services accessible from the internet, including:

Remote access from WAN
Port forwarding
DDNS
VPN server
DMZ
Port triggering
FTP

These steps significantly reduce the attack surface but do not fully eliminate the risk.

To further mitigate exposure, ASUS emphasizes essential best practices:

“Use different, complex passwords for your wireless network and router administration page (at least 10 characters, include uppercase, numbers and symbols).”

The advisory also reminds users: