Zero-day vulnerability in 1756-EN2T Series A

Out-of-bounds write
CVE-2023-3595

Vulnerability details

Advisory: SB2023071512 - Multiple vulnerabilities in Rockwell Automation ControlLogix EtherNet/IP (ENIP) communication modules

Vulnerable component: 1756-EN2T Series A

CVE-ID: CVE-2023-3595

CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C

CWE-ID: CWE-787 - Out-of-bounds write

Description:

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing CIP messages. A remote attacker can send specially crafted CIP messages to ports 44818/TCP or 2222/UDP, trigger an out-of-bounds write and execute arbitrary code.

Note, the vulnerability is most likely being exploited in the wild.

External links:

https://www.dragos.com/blog/mitigating-cves-impacting-rockwell-automation-controllogix-firmware/

https://www.cisa.gov/news-events/ics-advisories/icsa-23-193-01

https://www.bleepingcomputer.com/news/security/rockwell-warns-of-new-apt-rce-exploit-targeting-critical-infrastructure/

About zero-day vulnerabilities

Zero-day vulnerability is an undisclosed vulnerability in software that hackers can exploit to compromise computer programs, gain unauthorized access to sensitive data, penetrate networks, etc. We consider vulnerability a zero-day when there is no solution provided from software vendor and the vulnerability is being actively exploited by malicious actors.

Zero-day candidate is a potential zero-day vulnerability in software which might have been used in targeted attacks, however there is no evidence to support this suggestion.