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Fencer Vulns
critical 9.8

CVE-2020-6990 json

Rockwell Automation MicroLogix 1400 Controllers Series B v21.001 and prior, Series A, all versions, MicroLogix 1100 Controller, all version…

published 2020-03-16 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-28130

cvss
9.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
5.9%
EPSS 5.9% chance of exploitation in 30 days, percentile 93%
public exploits
0
none known

Summary

Rockwell Automation MicroLogix 1400 Controllers Series B v21.001 and prior, Series A, all versions, MicroLogix 1100 Controller, all versions, RSLogix 500 Software v12.001 and prior, The cryptographic key utilized to help protect the account password is hard coded into the RSLogix 500 binary file. An attacker could identify cryptographic keys and use it for further cryptographic attacks that could ultimately lead to a remote attacker gaining unauthorized access to the controller.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-20-070-06 updated cvss 9.8

Rockwell Automation MicroLogix Controllers and RSLogix 500 Software

  • Rockwell Automation MicroLogix 1100 Controller Rockwell Automation RSLogix 500 Software <= 12.001 Rockwell Automation Series A Rockwell Automation Series B <= 21.001
    affected: mitigation “For MicroLogix 1400 series B controllers, Rockwell recommends affected users apply FRN 21.002 or later for MicroLogix 1400 Series B devices and use the enhanced password security feature.” compatibility.rockwellautomation.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
total
Assessed
5 mo ago

Exploit prediction

5.89% chance of exploitation in the next 30 days, higher than 93% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 10.0 AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected products

  • n/a Rockwell Automation MicroLogix 1400 Controllers Series B v21.001 and prior, Series A, all versions, MicroLogix 1100 Controller, all versions, RSLogix 500 Software v12.001 and prior

Classification

Weakness
  • CWE-321 Use of Hard-coded Cryptographic Key
  • CWE-798 Use of Hard-coded Credentials

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.