CVE-2021-22791 Explained : Impact and Mitigation
Discover the impact of CVE-2021-22791, a critical out-of-bounds write vulnerability in Schneider Electric's Modicon PLC controllers and simulators, leading to potential denial of service attacks.
A CWE-787 vulnerability has been identified in Schneider Electric's Modicon PLC controllers and simulators, potentially leading to a Denial of Service (DoS) attack when uploading a specially crafted project file.
Understanding CVE-2021-22791
This CVE identifies a critical vulnerability in various Schneider Electric Modicon PLC controllers and simulators, affecting their functionality and security.
What is CVE-2021-22791?
The vulnerability is classified as CWE-787: Out-of-bounds Write, allowing an attacker to disrupt the Modicon PLC controller or simulator by exploiting a flaw during the application update process.
The Impact of CVE-2021-22791
Exploitation of this vulnerability could result in a denial of service condition on the affected devices, hindering their normal operation and potentially causing disruptions in industrial settings.
Technical Details of CVE-2021-22791
This section provides detailed technical insights into the CVE-2021-22791 vulnerability.
Vulnerability Description
The vulnerability involves an out-of-bounds write issue that occurs when updating the controller application with a specially crafted project file.
Affected Systems and Versions
The vulnerability impacts a wide range of Schneider Electric products, including Modicon M580 CPU, Modicon M340 CPU, Modicon MC80, Modicon Momentum Ethernet CPU, PLC Simulators, Modicon Quantum CPU, and Modicon Premium CPU, across all versions.
Exploitation Mechanism
By sending a maliciously crafted project file to the affected Modicon PLC controllers or simulators, an attacker can trigger the out-of-bounds write vulnerability, leading to a denial of service condition.
Mitigation and Prevention
To address and prevent potential exploitation of CVE-2021-22791, users should take immediate action and implement long-term security practices.
Immediate Steps to Take
Users are advised to apply security patches and updates provided by Schneider Electric to mitigate the vulnerability effectively.
Long-Term Security Practices
Regularly monitor vendor security advisories and follow best practices for securing industrial control systems to enhance overall cybersecurity posture.
Patching and Updates
Ensure timely installation of security patches released by Schneider Electric to address the CVE-2021-22791 vulnerability and enhance the security of the affected devices.