CVE-2021-22800

Name: CVE-2021-22800
Creator: NVD / NIST
Published: 2022-02-11T18:15:09.213+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.99%

Last modified Jun 17, 2026

CVE-2021-22800 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. A CWE-20: Improper Input Validation vulnerability exists that could cause a Denial of Service when a crafted packet is sent to the controller over network port 1105/TCP. Affected Product: Modicon M218 Logic Controller (V5.1.0.6 and prior). EPSS estimates a 0.99% chance of exploitation in the next 30 days.

Description

A CWE-20: Improper Input Validation vulnerability exists that could cause a Denial of Service when a crafted packet is sent to the controller over network port 1105/TCP. Affected Product: Modicon M218 Logic Controller (V5.1.0.6 and prior)

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

0.99%

58.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-20

Affected Software

Vendor	Product	Versions
Schneider-Electric	Modicon M218 Firmware	<= 5.1.0.6

References

https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2021-285-04Patch, Vendor Advisory
https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2021-285-04Patch, Vendor Advisory

Timeline

Published: Feb 11, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-22800?

How severe is CVE-2021-22800?

CVE-2021-22800 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.99% probability of exploitation in the next 30 days.

How do I fix CVE-2021-22800?

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-2021-22800?

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

Scan your code now

Source: NVD / NIST