CVE-2022-40267

criticalpriority · track · 36EPSS 0.012 · 68 %ileEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
1.18% (68th) EPSS
CVSS 9.1 · critical
Is it mine?
164 products
Check your exposure
Who says so?
3 sources
cnnvd · enisa_euvd · cisa_csaf_ot

EPSS · scored 2026-10-27

Predictable Seed in Pseudo-Random Number Generator (PRNG) vulnerability in Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-xMy/z (x=32,64,80, y=T,R, z=ES,DS,ESS,DSS) with serial number 17X**** or later, and versions 1.280 and prior, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-xMy/z (x=32,64,80, y=T,R, z=ES,DS,ESS,DSS) with serial number 179**** and prior, and versions 1.074 and prior, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-xMy/z (x=32,64,96, y=T, z=D,DSS)) with serial number 17X**** or later, and versions 1.280 and prior, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-xMy/z (x=32,64,96, y=T, z=D,DSS)) with serial number 179**** and prior, and versions 1.074 and prior, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-32MT/DS-TS versions 1.280 and prior, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-32MT/DSS-TS versions 1.280 and prior, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-xMy/z (x=24,40,60, y=T,R, z=ES,ESS) versions 1.042 and prior, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-xMy/ES-A (x=24,40,60, y=T,R) versions 1.043 and prior, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-xMy/z (x=30,40,60,80, y=T,R, z=ES,ESS) versions 1.003 and prior, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-32MR/DS-TS versions 1.280 and prior, Mitsubishi Electric Corporation MELSEC iQ-R Series R00/01/02CPU versions 33 and prior, Mitsubishi Electric Corporation MELSEC iQ-R Series R04/08/16/32/120(EN)CPU versions 66 and prior allows a remote unauthenticated attacker to access the Web server function by guessing the random numbers used for authentication from several used random numbers.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

No vendor fix yet; a mitigation is available.

  • MitigationFX5S-xMy/z* x=30,40,60,80, y=T,R, z=ES,ESScisa_csaf_ot

    "1.13 Security" - "IP filter" in the MELSEC iQ-R Ethernet User's Manual (Application)

  • MitigationFX5U-xMy/z x=32,64,80, y=T,R, z=ES,DS,ESS,DSScisa_csaf_ot

    "1.13 Security" - "IP filter" in the MELSEC iQ-R Ethernet User's Manual (Application)

  • MitigationFX5UC-xMy/z x=32,64,96 y=T, z=D,DSScisa_csaf_ot

    "1.13 Security" - "IP filter" in the MELSEC iQ-R Ethernet User's Manual (Application)

  • MitigationFX5UJ-xMy/ES-A* x=24,40,60, y=T,Rcisa_csaf_ot

    "1.13 Security" - "IP filter" in the MELSEC iQ-R Ethernet User's Manual (Application)

  • MitigationFX5UJ-xMy/z x=24,40,60, y=T,R, z=ES,ESScisa_csaf_ot

    "1.13 Security" - "IP filter" in the MELSEC iQ-R Ethernet User's Manual (Application)

  • MitigationMELSEC iQ-F Series FX5UC-32MT/DS-TS, FX5UC-32MT/DSS-TS, FX5UC-32MR/DS-TScisa_csaf_ot

    "1.13 Security" - "IP filter" in the MELSEC iQ-R Ethernet User's Manual (Application)

  • MitigationMELSEC iQ-R Series R04/08/16/32/120(EN)CPUcisa_csaf_ot

    "1.13 Security" - "IP filter" in the MELSEC iQ-R Ethernet User's Manual (Application)

  • MitigationMELSEC iQ-R series R00/01/02CPUcisa_csaf_ot

    "1.13 Security" - "IP filter" in the MELSEC iQ-R Ethernet User's Manual (Application)

02

cvss

Technical severity, 0–10. One row per scoring source.

9.1
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 5.9–9.1

v3.19.1criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 5.2
v3.05.9mediumCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · CISA US
v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · ENISA EU
v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · Mitsubishielectric.Psirt@yd.MitsubishiElectric.co.jpexploitability 2.2 · impact 3.6
v3.18.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

05

affected products (164)

Products and version ranges known to be affected.

showing 20 of 164
06

advisories (1)

Vendor and ecosystem advisories describing this.

07

also known as (3)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

published 2023-01-20modified 2026-06-17
10

references (12)

External citations — patches, advisories, analysis.

scry

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