What is CVE-2021-30187?

CVE-2021-30187 is a medium-severity vulnerability in Codesys Runtime Toolkit, classified under OS Command Injection. CVSS score: 5.3/10. Published 2021-05-25.

How severe is CVE-2021-30187?

Medium severity. CVSS v3 base score is 5.3 out of 10.

RCE in Codesys Runtime Toolkit

CVE-2021-30187

CODESYS V2 runtime system SP before 2.4.7.55 has Improper Neutralization of Special Elements used in an OS Command.

Vulnerability class: Command Injection (OS Command Injection)

Published 2021-05-25 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L.

EPSS exploit prediction

EPSS: 0.003 (17.1th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 17th percentile — 17.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-78 — OS Command Injection

References

customers.codesys.com/index.php (Permissions Required, Vendor Advisory)
customers.codesys.com/index.php (Vendor Advisory)

Frequently asked questions

What is CVE-2021-30187?: CVE-2021-30187 is a medium-severity vulnerability in Codesys Runtime Toolkit, classified under OS Command Injection. CVSS score: 5.3/10. Published 2021-05-25.
How severe is CVE-2021-30187?: Medium severity. CVSS v3 base score is 5.3 out of 10.