CVE-2021-4039

Public Exploit

Description

A command injection vulnerability in the web interface of the Zyxel NWA-1100-NH firmware could allow an attacker to execute arbitrary OS commands on the device.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 83.48% Top 5%
Vendor Advisory zyxel.com
Affected: Zyxel NWA1100-NH firmware
Published at:
Updated at:

References

Link Tags
https://www.zyxel.com/support/OS-command-injection-vulnerability-of-NWA1100-NH-access-point.shtml patch vendor advisory
http://packetstormsecurity.com/files/166752/Zyxel-NWA-1100-NH-Command-Injection.html release notes vdb entry exploit third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-4039?
CVE-2021-4039 has been scored as a critical severity vulnerability.
How to fix CVE-2021-4039?
To fix CVE-2021-4039, 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-2021-4039 being actively exploited in the wild?
It is possible that CVE-2021-4039 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~83% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-4039?
CVE-2021-4039 affects Zyxel NWA1100-NH firmware.
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