CVE-2023-28771

Known Exploited Public Exploit

Description

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 through 5.35, which could allow an unauthenticated attacker to execute some OS commands remotely by sending crafted packets to an affected device.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
EPSS 94.35% Top 5%
KEV Since 
Vendor Advisory zyxel.com
Affected: Zyxel ZyWALL/USG series firmware
Affected: Zyxel VPN series firmware
Affected: Zyxel USG FLEX series firmware
Affected: Zyxel ATP series firmware
Published at:
Updated at:

References

Link Tags
https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-remote-command-injection-vulnerability-of-firewalls vendor advisory
http://packetstormsecurity.com/files/172820/Zyxel-IKE-Packet-Decoder-Unauthenticated-Remote-Code-Execution.html third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2023-28771?
CVE-2023-28771 has been scored as a critical severity vulnerability.
How to fix CVE-2023-28771?
To fix CVE-2023-28771, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-28771 being actively exploited in the wild?
It is confirmed that CVE-2023-28771 is actively exploited. Be extra cautious if you are using vulnerable components. According to its EPSS score, there is a ~94% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-28771?
CVE-2023-28771 affects Zyxel ZyWALL/USG series firmware, Zyxel VPN series firmware, Zyxel USG FLEX series firmware, Zyxel ATP series firmware.
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