Mitsubishi Electric MELSEC-Q Q03UDVCPU length parameter

CVSS Meta Temp Score
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Mitsubishi Electric MELSEC-Q Q03UDVCPU, MELSEC-Q Q04UDVCPU, MELSEC-Q Q06UDVCPU, MELSEC-Q Q13UDVCPU, MELSEC-Q Q26UDVCPU, MELSEC-Q Q04UDPVCPU, MELSEC-Q Q06UDPVCPU, MELSEC-Q Q13UDPVCPU and MELSEC-Q Q26UDPVCPU. The affected element is an unknown function. Executing a manipulation can lead to length parameter. This vulnerability is tracked as CVE-2025-8531. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability has been found in Mitsubishi Electric MELSEC-Q Q03UDVCPU, MELSEC-Q Q04UDVCPU, MELSEC-Q Q06UDVCPU, MELSEC-Q Q13UDVCPU, MELSEC-Q Q26UDVCPU, MELSEC-Q Q04UDPVCPU, MELSEC-Q Q06UDPVCPU, MELSEC-Q Q13UDPVCPU and MELSEC-Q Q26UDPVCPU and classified as critical. This vulnerability affects some unknown functionality. The manipulation with an unknown input leads to a length parameter vulnerability. The CWE definition for the vulnerability is CWE-130. The product parses a formatted message or structure, but it does not handle or incorrectly handles a length field that is inconsistent with the actual length of the associated data. As an impact it is known to affect availability. CVE summarizes:

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.

The advisory is shared for download at mitsubishielectric.com. This vulnerability was named CVE-2025-8531 since 08/04/2025. The exploitation appears to be difficult. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-30300). Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.9
VulDB Temp Score: 5.9
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.8
CNA Vector (Mitsubishi): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Length parameter
CWE: CWE-130 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/04/2025 CVE reserved
09/19/2025 +46 days Advisory disclosed
09/19/2025 +0 days VulDB entry created
09/24/2025 +5 days VulDB entry last update

Sourcesinfo

Advisory: mitsubishielectric.com
Status: Confirmed

CVE: CVE-2025-8531 (🔒)
GCVE (CVE): GCVE-0-2025-8531
GCVE (VulDB): GCVE-100-325012
EUVD: 🔒

Entryinfo

Created: 09/19/2025 13:30
Updated: 09/24/2025 15:17
Changes: 09/19/2025 13:30 (59), 09/24/2025 15:17 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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