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Fencer Intel
critical 9.8

CVE-2020-5594 json

Mitsubishi Electric MELSEC iQ-R, iQ-F, Q, L, and FX series CPU modules all versions contain a vulnerability that allows cleartext transmiss…

published 6y ago modified 4mo ago also EUVD-2020-26755

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.3%
EPSS 1.3% chance of exploitation in 30 days, percentile 71%
public exploits
0
none known

Summary

Mitsubishi Electric MELSEC iQ-R, iQ-F, Q, L, and FX series CPU modules all versions contain a vulnerability that allows cleartext transmission of sensitive information between CPU modules and GX Works3 and/or GX Works2 via unspecified vectors.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-20-175-01 updated cvss 10.0

Mitsubishi Electric MELSEC iQ-R, iQ-F, Q, L and FX Series CPU Modules (Update A)

  • Mitsubishi Electric MELSEC iQ-R iQ-F Q L and FX series CPU modules
    affected: mitigation “Mitsubishi Electric recommends encrypting the communication path by setting up a VPN to mitigate the impact of this vulnerability.” us.mitsubishielectric.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

Exploit prediction

1.33% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

  • Mitsubishi Electric Corporation MELSEC iQ-R, iQ-F, Q, L, and FX series CPU modules

Classification

Weakness
  • CWE-319 Cleartext Transmission of Sensitive Information

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.