CVE-2020-5531

CVE-2020-5531 is a critical-severity vulnerability in Mitsubishielectric Mi5122-vw Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

Mitsubishi Electric MELSEC C Controller Module and MELIPC Series MI5000 MELSEC-Q Series C Controller Module(Q24DHCCPU-V, Q24DHCCPU-VG User Ethernet port (CH1, CH2): First 5 digits of serial number 21121 or before), MELSEC iQ-R Series C Controller Module / C Intelligent Function Module(R12CCPU-V Ethernet port (CH1, CH2): First 2 digits of serial number 11 or before, and RD55UP06-V Ethernet port: First 2 digits of serial number 08 or before), and MELIPC Series MI5000(MI5122-VW Ethernet port (CH1): First 2 digits of serial number 03 or before, or the firmware version 03 or before) allow remote attackers to cause a denial of service and/or malware being executed via unspecified vectors.

Frequently asked questions

What is CVE-2020-5531?
Mitsubishi Electric MELSEC C Controller Module and MELIPC Series MI5000 MELSEC-Q Series C Controller Module(Q24DHCCPU-V, Q24DHCCPU-VG User Ethernet port (CH1, CH2): First 5 digits of serial number 21121 or before), MELSEC iQ-R Series C Controller Module / C Intelligent Function Module(R12CCPU-V Ethernet port (CH1, CH2): First 2 digits of serial number 11 or before, and RD55UP06-V Ethernet port: First 2 digits of serial number 08 or before), and MELIPC Series MI5000(MI5122-VW Ethernet port (CH1): First 2 digits of serial number 03 or before, or the firmware version 03 or before) allow remote attackers to cause a denial of service and/or malware being executed via unspecified vectors.
How severe is CVE-2020-5531?
CVE-2020-5531 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-5531 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5531?
CVE-2020-5531 primarily affects Mitsubishielectric Mi5122-vw Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-5531?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-5531 published?
CVE-2020-5531 was published on 2020-02-17 and last updated on 2026-06-17.

References

Affected products (5)