CVE-2025-8531 Integer overflow in MELSEC-Q Series Q03UDVCPU
Remote attackers can cause denial of service in Mitsubishi MELSEC-Q PLCs via integer underflow when user authentication is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-8531?
CVE-2025-8531 is a medium-severity vulnerability in Mitsubishi Electric Corporation MELSEC-Q Series Q03UDVCPU, published on 19 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-130
Which versions are affected by CVE-2025-8531?
How do I fix CVE-2025-8531?
No fix has been published for CVE-2025-8531 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-8531 being exploited?
There is no known exploitation of CVE-2025-8531 in the wild and no public exploit code.
Sources
Also known as GHSA-r7hp-8xqq-gfpr.