CRITICAL

CVE-2021-40084

CVSS v3

9.8

CRITICAL

EPSS Score

2.9 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2021-40084 yet.

Full record on NVD

Description

opensysusers through 0.6 does not safely use eval on files in sysusers.d that may contain shell metacharacters. For example, it allows command execution via a crafted GECOS field whereas systemd-sysusers (a program with the same specification) does not do that.

Technical details

Published: 2021-08-25

Frequently asked questions

What is CVE-2021-40084?

Is CVE-2021-40084 actively exploited?

Active exploitation of CVE-2021-40084 has not been confirmed. Its EPSS score was 2.9% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-40084?

CVE-2021-40084 has a CVSS v3 base score of 9.8 (CRITICAL severity).

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