CVE-2025-8531: Medium severity Mitsubishi Electric MELSEC-Q Series Q03UDVCPU vulnerability

Published Sep 19, 2025
·
Updated

Improper Handling of Length Parameter Inconsistency vulnerability in Mitsubishi Electric Corporation MELSEC-Q Series Q03UDVCPU, Q04UDVCPU, Q06UDVCPU, Q13UDVCPU, Q26UDVCPU, Q04UDPVCPU, Q06UDPVCPU, Q13UDPVCPU, and Q26UDPVCPU with the first 5 digits of serial No. "24082" to "27081" allows a remote attacker to cause an integer underflow by sending specially crafted packets to the affected product to stop Ethernet communication and the execution of control programs on the product, when the user authentication function is enabled. The user authentication function is enabled by default only when settings are configured by GX Works2, which complies with the Cybersecurity Law of the People's Republic of China, and is normally disabled.

Affected Software

18 affected components
Mitsubishi Electric MELSEC-Q Series Q03UDVCPU
Mitsubishi Electric MELSEC-Q Series Q04UDVCPU
Mitsubishi Electric MELSEC-Q Series Q06UDVCPU
Mitsubishi Electric MELSEC-Q Series Q13UDVCPU
Mitsubishi Electric MELSEC-Q Series Q26UDVCPU
Mitsubishi Electric MELSEC-Q Series Q04UDPVCPU
Mitsubishi Electric MELSEC-Q Series Q06UDPVCPU
Mitsubishi Electric MELSEC-Q Series Q13UDPVCPU
Mitsubishi Electric MELSEC-Q Series Q26UDPVCPU
: Mitsubishi Electric MELSEC-Q Series Q03UDVCPU: The first 5 digits of serial No. '24082' to '27081'
: Mitsubishi Electric MELSEC-Q Series Q04UDVCPU: The first 5 digits of serial No. '24082' to '27081'
: Mitsubishi Electric MELSEC-Q Series Q06UDVCPU: The first 5 digits of serial No. '24082' to '27081'
: Mitsubishi Electric MELSEC-Q Series Q13UDVCPU: The first 5 digits of serial No. '24082' to '27081'
: Mitsubishi Electric MELSEC-Q Series Q26UDVCPU: The first 5 digits of serial No. '24082' to '27081'
: Mitsubishi Electric MELSEC-Q Series Q04UDPVCPU: The first 5 digits of serial No. '24082' to '27081'
: Mitsubishi Electric MELSEC-Q Series Q06UDPVCPU: The first 5 digits of serial No. '24082' to '27081'
: Mitsubishi Electric MELSEC-Q Series Q13UDPVCPU: The first 5 digits of serial No. '24082' to '27081'
: Mitsubishi Electric MELSEC-Q Series Q26UDPVCPU: The first 5 digits of serial No. '24082' to '27081'

Event History

Sep 19, 2025
CVE Published
via MITRE·09:30 AM
Data Sourced
via MITRE·09:30 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·10:15 AM
DescriptionSeverityWeakness
Sep 24, 2025
Data Sourced
via ICS·06:48 AM
SeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2025-8531?

CVE-2025-8531 has been classified with a critical severity level due to the potential impact of remote exploitation.

2

How do I fix CVE-2025-8531?

To fix CVE-2025-8531, update the firmware of the affected Mitsubishi Electric MELSEC-Q Series devices to the latest version provided by the vendor.

3

Which devices are affected by CVE-2025-8531?

CVE-2025-8531 affects various models of Mitsubishi Electric MELSEC-Q Series CPUs, specifically those with serial numbers from "24082" to "27081".

4

Can CVE-2025-8531 be exploited remotely?

Yes, CVE-2025-8531 can be exploited remotely, allowing attackers to manipulate device operations without physical access.

5

Is there a workaround for CVE-2025-8531?

As a temporary workaround for CVE-2025-8531, it is advisable to disable remote access features until the firmware is updated.

Contact

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