Zyxel ATP, USG FLEX, VPN, and ZyWALL/USG firewalls allow for improper error message handling which could allow an unauthenticated attacker to execute OS commands remotely by sending crafted packets to an affected device.
Zyxel ยท Multiple Firewalls
Known ransomware use: Unknown
Follow the source advisory and validate exposure in your environment.
Apply updates per vendor instructions.
Recent reporting that mentions CVE-2023-28771.
Hackers are performing widespread exploitation of a critical-severity command injection flaw in Zyxel networking devices, tracked as CVE-2023-28771, to install malware. [...]