CVE-2021-4039
CVSS v3
9.8
CRITICAL
EPSS Score
71.0 %
exploit probability, as of 2026-10-05
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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.
Technical details
- Published
- 2022-03-01
- Exploit-DB
- EDB-50870
Frequently asked questions
What is CVE-2021-4039?
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.
Is CVE-2021-4039 actively exploited?
Active exploitation of CVE-2021-4039 has not been confirmed. Its EPSS score was 71.0% on 2026-10-05, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-4039?
CVE-2021-4039 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-4039 affecting your environment?
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