CVE-2018-20021 Explained : Impact and Mitigation

LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835 vulnerability in the VNC client code, leading to an infinite loop, allowing attackers to exhaust CPU and RAM resources.

Understanding CVE-2018-20021

The vulnerability in LibVNC could result in a Denial of Service (DoS) attack, impacting system performance and stability.

What is CVE-2018-20021?

The VNC client code in LibVNC, before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c, has a CWE-835 vulnerability, causing an infinite loop that can be exploited by attackers to consume excessive CPU and RAM resources.

The Impact of CVE-2018-20021

Exploiting this vulnerability can lead to a DoS condition, affecting system availability and performance by overwhelming CPU and RAM resources.

Technical Details of CVE-2018-20021

The technical aspects of the CVE-2018-20021 vulnerability are as follows:

Vulnerability Description

LibVNC's VNC client code before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c
CWE-835: Infinite loop vulnerability

Affected Systems and Versions

Product: LibVNC
Version: commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c

Exploitation Mechanism

Attackers exploit the infinite loop in the VNC client code to consume excessive CPU and RAM resources.

Mitigation and Prevention

To address CVE-2018-20021, consider the following mitigation strategies:

Immediate Steps to Take

Update LibVNC to a version beyond commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c
Monitor system resources for unusual consumption
Implement network segmentation to limit the impact of potential DoS attacks

Long-Term Security Practices

Regularly update software and apply security patches
Conduct security audits to identify and address vulnerabilities

Patching and Updates

Stay informed about security advisories and updates from vendors
Apply patches promptly to mitigate known vulnerabilities