RCE in Zyxel Atp Series Firmware

CVE-2023-28771

Improper error message handling in Zyxel ZyWALL/USG series firmware versions 4.60 through 4.73, VPN series firmware versions 4.60 through 5.35, USG FLEX series firmware versions 4.60 through 5.35, and ATP series firmware versions 4.60 thro…

Vulnerability class: Command Injection (OS Command Injection)

EPSS: 0.943 (100.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: .

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2023-28771?
CVE-2023-28771 is a critical-severity vulnerability in Zyxel Atp Series Firmware, classified under OS Command Injection. CVSS score: 9.8/10. Published 2023-04-25.
How severe is CVE-2023-28771?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2023-28771 known to be exploited?
Yes. CVE-2023-28771 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-05-31), indicating it is being actively exploited. 16 public proof-of-concept repositories are indexed.