CVE-2022-40267

Authentication Bypass Vulnerability in Web Server Function on MELSEC Series

No known exploitation. EPSS puts it in the 66th percentile. Only a workaround so far.

CVSS 3.15.9Medium EPSS percentile66th1.2% chance in 30 days CISA KEVNot listedNo confirmed exploitation
No public exploit known FixWorkaroundNo fixed build yet

Published 2023-01-20Updated 2024-11-21Sources: CVE.org, NVD, CSAF

NVD CVE.org

What to do

No fixed build is published yet. The vendor describes a workaround.

What it is

From the CVE record

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.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS66th

CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

1.2% chance of exploitation activity in the next 30 days, which ranks it in the 66th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

4 events over 671 days, from the signal feeds we watch.

2024-11-21Workaround availablerecord updated
2023-01-20Publishedweakness classified

Affected products

And 104 more affected products. See all after sign-in

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Scored 5.9 by NVD.

How it is reached

Attack Vector NetworkExploitable remotely over the network without any special conditions
Attack Complexity HighRequires specific conditions like a race condition or non-default configuration
Privileges Required NoneNo authentication required — anyone can exploit this
User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

Confidentiality NoneNo confidentiality impact
Integrity HighTotal loss of integrity — attacker can modify any data in the component
Availability NoneNo availability impact

Weaknesses

Sources

References in the record

And 9 more references. See all after sign-in

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