How severe is CVE-2020-6986?

CVE-2020-6986 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-2020-6986 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-6986?

CVE-2020-6986 primarily affects Omron Plc Cj1 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-6986?

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-2020-6986 published?

CVE-2020-6986 was published on 2020-03-05 and last updated on 2026-06-17.

CVE-2020-6986

CVE-2020-6986 is a high-severity vulnerability in Omron Plc Cj1 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: 2% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Omron Plc Cj1 Firmware
Published: 2020-03-05
Last modified: 2026-06-17

Description

In all versions of Omron PLC CJ Series, an attacker can send a series of specific data packets within a short period, causing a service error on the PLC Ethernet module, which in turn causes a PLC service denied result.

Frequently asked questions

What is CVE-2020-6986?: In all versions of Omron PLC CJ Series, an attacker can send a series of specific data packets within a short period, causing a service error on the PLC Ethernet module, which in turn causes a PLC service denied result.
How severe is CVE-2020-6986?: CVE-2020-6986 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-2020-6986 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-6986?: CVE-2020-6986 primarily affects Omron Plc Cj1 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-6986?: 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-2020-6986 published?: CVE-2020-6986 was published on 2020-03-05 and last updated on 2026-06-17.

References

https://www.us-cert.gov/ics/advisories/icsa-20-063-03

Affected products (2)

cpe:2.3:o:omron:plc_cj1_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:omron:plc_cj2_firmware:*:*:*:*:*:*:*:*

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