CVE-2021-42979 : Exploit Details and Defense Strategies

NoMachine Cloud Server is affected by an Integer Overflow vulnerability that allows local attackers to execute arbitrary code in kernel mode or cause a denial of service. This CVE has a CVSS score of 7.0.

Understanding CVE-2021-42979

NoMachine Cloud Server is impacted by an Integer Overflow vulnerability in the IOCTL Handler.

What is CVE-2021-42979?

The Integer Overflow vulnerability in NoMachine Cloud Server allows attackers to trigger memory corruption or OS crashes by exploiting a specific I/O Request Packet.

The Impact of CVE-2021-42979

This vulnerability can lead to local attackers executing arbitrary code in kernel mode or disrupting the service, potentially resulting in a denial of service (DoS) incident.

Technical Details of CVE-2021-42979

NoMachine Cloud Server's vulnerability details are as follows:

Vulnerability Description

Integer overflow in IOCTL Handler 0x22001B
Affects versions above 4.0.346 and below 7.7.4

Affected Systems and Versions

NoMachine Cloud Server
Versions above 4.0.346 and below 7.7.4

Exploitation Mechanism

Attackers can craft malicious I/O Request Packets to trigger the vulnerability

Mitigation and Prevention

To mitigate CVE-2021-42979, consider the following steps:

Immediate Steps to Take

Update NoMachine Cloud Server to a patched version
Monitor for any unusual activity on the system

Long-Term Security Practices

Implement the principle of least privilege for users
Regularly update and patch software and systems

Patching and Updates

Apply the security patches provided by NoMachine for the Cloud Server