CVE-2020-6986

highpriority · track · 31EPSS 0.016 · 75 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.56% (75th) EPSS

CVSS 7.8 · high

Is it mine?

5 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cisa_csaf_ot · nvd

EPSS · scored 2026-10-27

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.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

No vendor fix yet; a mitigation is available.

MitigationOmron PLC CJ Seriescisa_csaf_ot
Filter FINS port: Protect access to Omron's PLC with a firewall and by blocking unnecessary remote access to FINS port (default: 9600).

cvss

Technical severity, 0–10. One row per scoring source.

7.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.8

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · CISA US

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 3.9 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USprimaryCWE-400US

affected products (5)

Products and version ranges known to be affected.

Omron PLC CJ series: all versionsall versionscisa_csaf_otUS
Omron Omron PLC CJ Seriesall versionscisa_csaf_otUS
n/a Omron PLC CJ Series≤ all versionsenisa_euvdEU
omron plc cj1 firmwareall versionsnvdUScpe:2.3:o:omron:plc_cj1_firmware:*:*:*:*:*:*:*:*
omron plc cj2 firmwareall versionsnvdUScpe:2.3:o:omron:plc_cj2_firmware:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-20-063-03Omron PLC CJ Series2020-03-03icsa · cisa_csaf_otUS
Successful exploitation of this vulnerability could cause a denial-of-service condition.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cisa_csaf_ot nvd NVD CVE.org MITRE

published 2020-03-05modified 2026-06-17

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+9613 more

references (6)

External citations — patches, advisories, analysis.

http://www.nsfocus.net/vulndb/46077 cnnvd
https://nvd.nist.gov/vuln/detail/CVE-2020-6986 cnnvd
https://www.auscert.org.au/bulletins/ESB-2020.0779/cnnvd
https://www.us-cert.gov/ics/advisories/icsa-20-063-03 cnnvd
https://www.us-cert.gov/ics/advisories/icsa-20-063-03 enisa_euvd
https://www.us-cert.gov/ics/advisories/icsa-20-063-03MitigationThird Party AdvisoryUS Government Resourcenvd

scry

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