How severe is CVE-2020-13238?

CVE-2020-13238 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-2020-13238 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-13238?

CVE-2020-13238 primarily affects Mitsubishielectric Melsec Iq-r00cpu Firmware. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-13238?

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-2020-13238 published?

CVE-2020-13238 was published on 2020-06-10 and last updated on 2026-06-17.

CVE-2020-13238

CVE-2020-13238 is a high-severity vulnerability in Mitsubishielectric Melsec Iq-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-400.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Mitsubishielectric Melsec Iq-r00cpu Firmware
Published: 2020-06-10
Last modified: 2026-06-17

Description

Mitsubishi MELSEC iQ-R Series PLCs with firmware 33 allow attackers to halt the industrial process by sending an unauthenticated crafted packet over the network, because this denial of service attack consumes excessive CPU time. After halting, physical access to the PLC is required in order to restore production.

Frequently asked questions

What is CVE-2020-13238?: Mitsubishi MELSEC iQ-R Series PLCs with firmware 33 allow attackers to halt the industrial process by sending an unauthenticated crafted packet over the network, because this denial of service attack consumes excessive CPU time. After halting, physical access to the PLC is required in order to restore production.
How severe is CVE-2020-13238?: CVE-2020-13238 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-2020-13238 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-13238?: CVE-2020-13238 primarily affects Mitsubishielectric Melsec Iq-r00cpu Firmware. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-13238?: 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-2020-13238 published?: CVE-2020-13238 was published on 2020-06-10 and last updated on 2026-06-17.

References

Affected products (21)

cpe:2.3:o:mitsubishielectric:melsec_iq-r00cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r01cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r02cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r04cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r08cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r16cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r32cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r120cpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r08fcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r16fcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r32fcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r120fcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r08pcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r16pcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r32pcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r120pcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r08sfcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r16sfcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r32sfcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-r120sfcpu_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:mitsubishielectric:melsec_iq-rj71en71_firmware:*:*:*:*:*:*:*:*

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