How severe is CVE-2020-16850?

CVE-2020-16850 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-16850 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-16850?

CVE-2020-16850 primarily affects Mitsubishielectric R00cpu Firmware. In total, 19 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-16850?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-16850 published?

CVE-2020-16850 was published on 2020-11-30 and last updated on 2026-06-17.

CVE-2020-16850

CVE-2020-16850 is a high-severity vulnerability in Mitsubishielectric R00cpu Firmware with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mitsubishielectric R00cpu Firmware
Published: 2020-11-30
Last modified: 2026-06-17

Description

Mitsubishi MELSEC iQ-R Series PLCs with firmware 49 allow an unauthenticated attacker to halt the industrial process by sending a crafted packet over the network. This denial of service attack exposes Improper Input Validation. After halting, physical access to the PLC is required in order to restore production, and the device state is lost. This is related to R04CPU, RJ71GF11-T2, R04CPU, and RJ71GF11-T2.

Frequently asked questions

What is CVE-2020-16850?: Mitsubishi MELSEC iQ-R Series PLCs with firmware 49 allow an unauthenticated attacker to halt the industrial process by sending a crafted packet over the network. This denial of service attack exposes Improper Input Validation. After halting, physical access to the PLC is required in order to restore production, and the device state is lost. This is related to R04CPU, RJ71GF11-T2, R04CPU, and RJ71GF11-T2.
How severe is CVE-2020-16850?: CVE-2020-16850 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-16850 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-16850?: CVE-2020-16850 primarily affects Mitsubishielectric R00cpu Firmware. In total, 19 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-16850?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-16850 published?: CVE-2020-16850 was published on 2020-11-30 and last updated on 2026-06-17.

References

Affected products (19)

cpe:2.3:o:mitsubishielectric:r00cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r01cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r02cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r04cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r08cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r16cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r32cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r120cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r08sfcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r16sfcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r32sfcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r120sfcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r08pcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r16pcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r32pcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r120pcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r16mtcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r32mtcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:r64mtcpu_firmware:*:*:*:*:*:*:*:*

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