CVE-2023-28771: Zyxel Multiple Firewalls OS Command Injection Vulnerability

CISA Known Exploited Vulnerability (KEV)

Description

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.

Required action (CISA)

Apply updates per vendor instructions.

Notes

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-remote-command-injection-vulnerability-of-firewalls; https://nvd.nist.gov/vuln/detail/CVE-2023-28771

Weakness behind it

CISA records this vulnerability as an instance of CWE-78. From there the chain continues into CAPEC attack patterns and ATT&CK techniques, all inside this corpus.

References

• NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-28771
• KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog