CVE-2025-8531 (CVSS 6.8)

Description

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.

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CVSS v3.1 Score

6.8

MEDIUM

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

Weakness Type (CWE)

CWE-130 CWE-130

References

Other References

https://jvn.jp/vu/JVNVU97846038/ https://www.cisa.gov/news-events/ics-advisories/icsa-25-266-02 https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2025-013_en.pdf

Frequently Asked Questions

What is CVE-2025-8531? +

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. It has a CVSS v3.1 base score of 6.8 (MEDIUM).

How severe is CVE-2025-8531? +

CVE-2025-8531 has a CVSS v3.1 score of 6.8 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2025-8531? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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