CVE-2021-20607

Denial of service via crafted project file

Published Dec 17, 2021 · Updated Aug 3, 2024

Integer underflow in Mitsubishi Electric GX Works2, MELSOFT Navigator, and EZSocket allows attackers to cause a denial of service. Mitsubishi Electric has not disclosed the parsing locus or arithmetic operation that underflows when a crafted project file is opened. GX Works2 1.606G and earlier, MELSOFT Navigator 2.84N and earlier, and EZSocket 5.4 and earlier are affected; exploitation requires a user to open the attacker-crafted file, after which the software enters a denial-of-service condition.

CVSS severity5.5
Medium
EPSS probability0.93%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer underflow in Mitsubishi Electric GX Works2, MELSOFT Navigator, and EZSocket allows attackers to cause a denial of service. Mitsubishi Electric has not disclosed the parsing locus or arithmetic operation that underflows when a crafted project file is opened. GX Works2 1.606G and earlier, MELSOFT Navigator 2.84N and earlier, and EZSocket 5.4 and earlier are affected; exploitation requires a user to open the attacker-crafted file, after which the software enters a denial-of-service condition.

The record

CVE
CVE-2021-20607
Published
Dec 17, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-191, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 17, 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

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
5.5Mitsubishi Electric CorporationCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

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.

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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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-191Integer Underflow (Wrap or Wraparound)
T1204.002Malicious File

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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