CVE-2021-33012

Published: Jul 9, 2021Updated: Jun 3, 2026 Sources: CVE List NVD csafCWE-20

8.6HIGH

NVD MITRE

Description

Rockwell Automation MicroLogix 1100, all versions, allows a remote, unauthenticated attacker sending specially crafted commands to cause the PLC to fault when the controller is switched to RUN mode, which results in a denial-of-service condition. If successfully exploited, this vulnerability will cause the controller to fault whenever the controller is switched to RUN mode.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:CScope

Changed

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-20 NVD-CWE-noinfo

Affected Products

rockwellautomation

commercial·USaka rockwell automation

micrologix 1100 firmware

ICS / OT / IoT

and 1 more affected products View all →

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Initial Access

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References

https://us-cert.cisa.gov/ics/advisories/icsa-21-189-01

us-cert.cisa.gov

https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2021/icsa-21-189-01.json

raw.githubusercontent.com

https://www.cisa.gov/news-events/ics-advisories/icsa-21-189-01

cisa.gov

and 4 more references View all →

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