CVE-2021-30187

OS command execution via SysFile calls

Published May 25, 2021 · Updated Aug 3, 2024

Improper neutralization of special elements in CODESYS V2 runtime system SP before 2.4.7.55 allows remote authenticated users to execute OS functions through crafted PLC logic. The SysFile system library passes programmer-controlled values to operating-system functionality without adequate command-element neutralization. Exploitation requires PLC programming access, which is available when no online password is configured or after successful controller authentication; the resulting impact includes execution of additional local OS functions.

CVSS severity5.3
Medium
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper neutralization of special elements in CODESYS V2 runtime system SP before 2.4.7.55 allows remote authenticated users to execute OS functions through crafted PLC logic. The SysFile system library passes programmer-controlled values to operating-system functionality without adequate command-element neutralization. Exploitation requires PLC programming access, which is available when no online password is configured or after successful controller authentication; the resulting impact includes execution of additional local OS functions.

The record

CVE
CVE-2021-30187
Published
May 25, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-78, T1059
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 25, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.3NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
4.6NVDAV:L/AC:L/Au:N/C:P/I:P/A:P
5.3CODESYSCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo