Actively exploited in the wild
Zyxel Multiple NAS Devices Command Injection Vulnerability
Zyxel - Multiple Network-Attached Storage (NAS) Devices · Listed in the CISA KEV since 2023-06-23. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2023-27992
CriticalCVSS 9.8KEVSummary
Pre-authentication command injection vulnerability in Zyxel NAS326 firmware versions prior to V5.21(AAZF.14)C0, NAS540 prior to V5.21(AATB.11)C0, and NAS542 prior to V5.21(ABAG.11)C0. An unauthenticated attacker could execute OS commands remotely by sending a crafted HTTP request.
Risk Assessment
An unauthenticated attacker could take control of the NAS device, execute arbitrary commands, and access stored data.
Recommendation
Update Zyxel NAS firmware to the patched versions. Restrict management interface access from the Internet.
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Original NVD description (English source)
The pre-authentication command injection vulnerability in the Zyxel NAS326 firmware versions prior to V5.21(AAZF.14)C0, NAS540 firmware versions prior to V5.21(AATB.11)C0, and NAS542 firmware versions prior to V5.21(ABAG.11)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands remotely by sending a crafted HTTP request.