Zyxel DSL CPE OS Command Injection Vulnerability

[ Why it matters ]Priority signals

• Exploited in the wild: on CISA's Known Exploited Vulnerabilities list since 2025-02-11
• EPSS: 21% chance of exploitation in the next 30 days (higher than 98% of CVEs)

[ Description ]Official description

**UNSUPPORTED WHEN ASSIGNED** A post-authentication command injection vulnerability in the CGI program of the legacy DSL CPE Zyxel VMG4325-B10A firmware version 1.00(AAFR.4)C0_20170615 could allow an authenticated attacker to execute operating system (OS) commands on an affected device by sending a crafted HTTP POST request.

CISA: Multiple Zyxel DSL CPE devices contain a post-authentication command injection vulnerability in the CGI program that could allow an authenticated attacker to execute OS commands via a crafted HTTP request.

[ Fixes ]Fixes and patches

CISA required action (US federal deadline 4 Mar 2025): The impacted product could be end-of-life (EoL) and/or end-of-service (EoS). Users should discontinue product utilization if a current mitigation is unavailable.

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References

• www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-command…Vendor Advisory
• www.cisa.gov/known-exploited-vulnerabilities-catalogUS Government Resource