Vulnerability identifier: #VU54631

Vulnerability risk: Medium

CVSSv3.1: 6.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:U/RC:C]

CVE-ID: CVE-2021-33012

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Allen-Bradley MicroLogix 1100
Hardware solutions / Office equipment, IP-phones, print servers

Vendor: Rockwell Automation

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input within the PLC when the controller is switched to RUN mode. A remote attacker can pass specially crafted input to the application and perform a denial of service (DoS) attack.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Allen-Bradley MicroLogix 1100: All versions

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External links
http://ics-cert.us-cert.gov/advisories/icsa-21-189-01

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.