CVE-2021-30186

Name: CVE-2021-30186
Creator: NVD / NIST
Published: 2021-05-25T13:15:17.677+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 7.36%

Last modified Jun 17, 2026

CVE-2021-30186 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. CODESYS V2 runtime system SP before 2.4.7.55 has a Heap-based Buffer Overflow.. EPSS estimates a 7.36% chance of exploitation in the next 30 days.

Description

CODESYS V2 runtime system SP before 2.4.7.55 has a Heap-based Buffer Overflow.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

7.36%

93.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-787

Affected Software

Vendor	Product	Versions
Wago	750-893 Firmware	< fw08
Wago	750-891 Firmware	< fw08
Wago	750-890 Firmware	< fw08
Wago	750-889 Firmware	< fw15
Wago	750-885 Firmware	< fw15
Wago	750-882 Firmware	< fw15
Wago	750-881 Firmware	< fw15
Wago	750-880 Firmware	< fw16
Wago	750-862 Firmware	< fw08
Wago	750-852 Firmware	< fw15
Wago	750-832 Firmware	< fw08
Wago	750-831 Firmware	< fw15
Wago	750-829 Firmware	< fw15
Wago	750-8202 Firmware	< 03.06.19_\(18\)
Wago	750-8203 Firmware	< 03.06.19_\(18\)
Wago	750-8204 Firmware	< 03.06.19_\(18\)
Wago	750-8206 Firmware	< 03.06.19_\(18\)
Wago	750-8207 Firmware	< 03.06.19_\(18\)
Wago	750-8208 Firmware	< 03.06.19_\(18\)
Wago	750-8210 Firmware	< 03.06.19_\(18\)
Wago	750-8211 Firmware	< 03.06.19_\(18\)
Wago	750-8212 Firmware	< 03.06.19_\(18\)
Wago	750-8213 Firmware	< 03.06.19_\(18\)
Wago	750-8214 Firmware	< 03.06.19_\(18\)
Wago	750-8216 Firmware	< 03.06.19_\(18\)
Wago	750-8217 Firmware	< 03.06.19_\(18\)
Codesys	Plcwinnt	< 2.4.7.55
Codesys	Runtime Toolkit	< 2.4.7.55
Wago	750-823 Firmware	< fw08

References

https://customers.codesys.com/index.phpPermissions Required, Vendor Advisory
https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=14725&token=08691519ef764b252630759eff925890176ecd78&download=Vendor Advisory
https://customers.codesys.com/index.phpPermissions Required, Vendor Advisory
https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=14725&token=08691519ef764b252630759eff925890176ecd78&download=Vendor Advisory

Timeline

Published: May 25, 2021
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2021-30186?

CODESYS V2 runtime system SP before 2.4.7.55 has a Heap-based Buffer Overflow.

How severe is CVE-2021-30186?

CVE-2021-30186 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 7.36% probability of exploitation in the next 30 days.

How do I fix CVE-2021-30186?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-30186?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST