CVE-2022-45794: Network-based Manipulation of PLC Internal Memory and Memory Card

Overview

The cybersecurity world has recently been exposed to a new vulnerability, CVE-2022-45794. This vulnerability affects programmable logic controllers (PLCs) of the CJ-series and CS-series, irrespective of their versions. PLCs are crucial components in industrial control systems and automation, hence, their breach can lead to severe implications, including system compromise and potential data leakage. The gravity of this vulnerability lies in the fact that it allows an attacker with network access to read and write files on the PLC’s internal memory and memory card, potentially giving them control over the entire system.

Vulnerability Summary

CVE ID: CVE-2022-45794
Severity: High (8.6 CVSS score)
Attack Vector: Network-based
Privileges Required: Low
User Interaction: None
Impact: Potential system compromise and data leakage

Affected Products

Product | Affected Versions

CJ-series PLCs | All Versions
CS-series PLCs | All Versions

How the Exploit Works

The attacker, given they have network access, uses a specific network protocol to initiate the exploit. This protocol allows the attacker to send requests directly to the PLC, bypassing any existing security measures. Once the communication is established, the attacker can send commands to read or write files on the PLC’s internal memory and memory card. This access, if used maliciously, can lead to system compromise and data leakage.

Conceptual Example Code

Here is a conceptual representation of how the vulnerability might be exploited:

GET /plc/memory HTTP/1.1
Host: target.example.com
{ "command": "read", "filename": "/etc/passwd" }

In this example, the attacker sends a GET request to the PLC’s memory endpoint. The command “read” is issued along with the filename “/etc/passwd”, which is a common target for attackers seeking to gain unauthorized access to a system.

Mitigation Guidance

The best way to mitigate the impact of this vulnerability is to apply the vendor patch as soon as it becomes available. Until then, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) can serve as temporary mitigation. These systems can monitor network traffic and identify and block potential threats. Additionally, minimizing the number of people with network access to the PLCs can also help prevent exploitation.