Zyxel: Security Vulnerabilities
A post-authentication command injection vulnerability in the log file download function of the Zyxel EX3301-T0 firmware versions through 5.50(ABVY.7)C0 could allow an authenticated attacker to execute operating system (OS) commands on an affected device.
CVSS Score
8.8
EPSS Score
0.014
Published
2026-02-24
A post-authentication command injection vulnerability in the TR-369 certificate download CGI program of the Zyxel VMG3625-T50B firmware versions through 5.50(ABPM.9.7)C0 could allow an authenticated attacker with administrator privileges to execute operating system (OS) commands on an affected device.
CVSS Score
7.2
EPSS Score
0.009
Published
2026-02-24
A null pointer dereference vulnerability in the IP settings CGI program of the Zyxel VMG3625-T50B firmware versions through 5.50(ABPM.9.6)C0 and the Zyxel WX3100-T0 firmware versions through 5.50(ABVL.4.8)C0 could allow an authenticated attacker with administrator privileges to trigger a denial-of-service (DoS) condition by sending a crafted HTTP request.
CVSS Score
4.9
EPSS Score
0.018
Published
2026-02-24
A null pointer dereference vulnerability in the account settings CGI program of the Zyxel VMG3625-T50B firmware versions through 5.50(ABPM.9.6)C0 and the Zyxel WX3100-T0 firmware versions through 5.50(ABVL.4.8)C0 could allow an authenticated attacker with administrator privileges to trigger a denial-of-service (DoS) condition by sending a crafted HTTP request.
CVSS Score
4.9
EPSS Score
0.012
Published
2026-02-24
A null pointer dereference vulnerability in the certificate downloader CGI program of the Zyxel VMG3625-T50B firmware versions through 5.50(ABPM.9.6)C0 and the Zyxel WX3100-T0 firmware versions through 5.50(ABVL.4.8)C0 could allow an authenticated attacker with administrator privileges to trigger a denial-of-service (DoS) condition by sending a crafted HTTP request.
CVSS Score
4.9
EPSS Score
0.008
Published
2026-02-24
An uncontrolled resource consumption vulnerability in the web server of Zyxel DX3301-T0 firmware version 5.50(ABVY.6.3)C0 and earlier could allow an attacker to perform Slowloris‑style denial‑of‑service (DoS) attacks. Such attacks may temporarily block legitimate HTTP requests and partially disrupt access to the web management interface, while other networking services remain unaffected.
CVSS Score
5.3
EPSS Score
0.003
Published
2025-11-18
A post-authentication command injection vulnerability in the "priv" parameter of Zyxel DX3300-T0 firmware version 5.50(ABVY.6.3)C0 and earlier could allow an authenticated attacker to execute operating system (OS) commands on an affected device.
CVSS Score
8.8
EPSS Score
0.011
Published
2025-11-18
A missing authorization vulnerability in Zyxel ATP series firmware versions from V4.32 through V5.40, USG FLEX series firmware versions from V4.50 through V5.40, USG FLEX 50(W) series firmware versions from V4.16 through V5.40, and USG20(W)-VPN series firmware versions from V4.16 through V5.40 could allow a semi-authenticated attacker—who has completed only the first stage of the two-factor authentication (2FA) process—to view and download the system configuration from an affected device.
CVSS Score
8.1
EPSS Score
0.055
Published
2025-10-21
A post-authentication command injection vulnerability in Zyxel ATP series firmware versions from V4.32 through V5.40, USG FLEX series firmware versions from V4.50 through V5.40, USG FLEX 50(W) series firmware versions from V4.16 through V5.40, and USG20(W)-VPN series firmware versions from V4.16 through V5.40 could allow an authenticated attacker with administrator privileges to execute operating system (OS) commands on the affected device by passing a crafted string as an argument to a CLI command.
CVSS Score
7.2
EPSS Score
0.014
Published
2025-10-21
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.
CVSS Score
9.8
EPSS Score
0.005
Published
2025-07-16