CVE-2021-20607

Name: CVE-2021-20607
Creator: NVD / NIST
Published: 2021-12-17T17:15:11.89+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.93%

Last modified Jun 17, 2026

CVE-2021-20607 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. Integer Underflow vulnerability in Mitsubishi Electric GX Works2 versions 1.606G and prior, Mitsubishi Electric MELSOFT Navigator versions 2.84N and prior and Mitsubishi Electric EZSocket versions 5.4 and prior allows an attacker to cause a DoS condition in the software by getting a user to open malicious project file specially crafted by an attacker.. EPSS estimates a 0.93% chance of exploitation in the next 30 days.

Description

Integer Underflow vulnerability in Mitsubishi Electric GX Works2 versions 1.606G and prior, Mitsubishi Electric MELSOFT Navigator versions 2.84N and prior and Mitsubishi Electric EZSocket versions 5.4 and prior allows an attacker to cause a DoS condition in the software by getting a user to open malicious project file specially crafted by an attacker.

Metrics

CVSS 3.1

5.5/10

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

EPSS Probability

0.93%

56.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-191

Affected Software

Vendor	Product	Versions
Mitsubishielectric	Ezsocket	<= 5.4
Mitsubishielectric	Gx Works2	<= 1.606g
Mitsubishielectric	Melsoft Navigator	All versions

References

https://jvn.jp/vu/JVNVU93817405/index.htmlPatch, Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-350-05Third Party Advisory, US Government Resource
https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-021_en.pdfPatch, Vendor Advisory
https://jvn.jp/vu/JVNVU93817405/index.htmlPatch, Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-350-05Third Party Advisory, US Government Resource
https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-021_en.pdfPatch, Vendor Advisory

Timeline

Published: Dec 17, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20607?

How severe is CVE-2021-20607?

CVE-2021-20607 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.93% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20607?

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-2021-20607?

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

Scan your code now

Source: NVD / NIST