CVE-2020-6111

Name: CVE-2020-6111
Creator: NVD / NIST
Published: 2020-12-03T13:15:10.477+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 4.58%

Last modified Jun 17, 2026

CVE-2020-6111 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. An exploitable denial-of-service vulnerability exists in the IPv4 functionality of Allen-Bradley MicroLogix 1100 Programmable Logic Controller Systems Series B FRN 16.000, Series B FRN 15.002, Series B FRN 15.000, Series B FRN 14.000, Series B FRN 13.000, Series B FRN 12.000, Series B FRN 11.000 and Series B FRN 10.000. A specially crafted packet can cause a major error, resulting in a denial of service. EPSS estimates a 4.58% chance of exploitation in the next 30 days.

Description

An exploitable denial-of-service vulnerability exists in the IPv4 functionality of Allen-Bradley MicroLogix 1100 Programmable Logic Controller Systems Series B FRN 16.000, Series B FRN 15.002, Series B FRN 15.000, Series B FRN 14.000, Series B FRN 13.000, Series B FRN 12.000, Series B FRN 11.000 and Series B FRN 10.000. A specially crafted packet can cause a major error, resulting in a denial of service. An attacker can send a malicious packet to trigger this vulnerability.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

4.58%

90.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-189

Affected Software

Vendor	Product	Versions
Rockwellautomation	Micrologix 1100 B Firmware	10.000
Rockwellautomation	Micrologix 1100 B Firmware	11.000
Rockwellautomation	Micrologix 1100 B Firmware	12.000
Rockwellautomation	Micrologix 1100 B Firmware	13.000
Rockwellautomation	Micrologix 1100 B Firmware	14.000
Rockwellautomation	Micrologix 1100 B Firmware	15.000
Rockwellautomation	Micrologix 1100 B Firmware	15.002
Rockwellautomation	Micrologix 1100 B Firmware	16.000

References

https://talosintelligence.com/vulnerability_reports/TALOS-2020-1057Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-047-02Third Party Advisory, US Government Resource
https://talosintelligence.com/vulnerability_reports/TALOS-2020-1057Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-047-02Third Party Advisory, US Government Resource

Timeline

Published: Dec 3, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-6111?

How severe is CVE-2020-6111?

CVE-2020-6111 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 4.58% probability of exploitation in the next 30 days.

How do I fix CVE-2020-6111?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-6111?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST