CVE-2022-40267
criticalpriority · track · 36EPSS 0.012 · 68 %ileEUUSEPSS · 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.
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)
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 5.9–9.1
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (164)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- ICSA-23-017-02Mitsubishi Electric MELSEC iQ-F, iQ-R Series2023-01-17icsa · cisa_csaf_otUS
These products are available in limited regions.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (12)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2022-40267/cnnvd
- https://jvn.jp/vu/JVNVU99673580/index.htmlcnnvd
- https://talosintelligence.com/vulnerability_reports/TALOS-2022-1646cnnvd
- https://www.cisa.gov/uscert/ics/advisories/icsa-23-017-02cnnvd
- https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2022-019_en.pdfcnnvd
- https://jvn.jp/vu/JVNVU99673580/index.htmlenisa_euvd
- https://www.cisa.gov/uscert/ics/advisories/icsa-23-017-02enisa_euvd
- https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2022-019_en.pdfenisa_euvd
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