CVE-2018-20843 : Security Advisory and Response

Expat library prior to version 2.2.7 has a vulnerability in the libexpat module that could lead to denial-of-service attacks due to excessive consumption of RAM and CPU resources.

Understanding CVE-2018-20843

The vulnerability in the Expat library could allow for denial-of-service attacks by exploiting XML input with names containing numerous colons.

What is CVE-2018-20843?

In Expat before version 2.2.7, XML input with XML names containing many colons could cause the XML parser to consume high RAM and CPU resources, making it susceptible to denial-of-service attacks.

The Impact of CVE-2018-20843

The vulnerability could result in excessive consumption of system resources, potentially leading to denial-of-service attacks.

Technical Details of CVE-2018-20843

The technical aspects of the vulnerability in the Expat library.

Vulnerability Description

The vulnerability in libexpat could allow attackers to exploit XML input with a large number of colons, causing the XML parser to consume significant system resources.

Affected Systems and Versions

Product: N/A
Vendor: N/A
Versions affected: < 2.2.7

Exploitation Mechanism

Attackers can craft XML input with names containing numerous colons to trigger excessive consumption of RAM and CPU resources during processing.

Mitigation and Prevention

Ways to address and prevent the CVE-2018-20843 vulnerability.

Immediate Steps to Take

Update Expat library to version 2.2.7 or newer to mitigate the vulnerability.
Monitor system resources for any unusual spikes in RAM or CPU usage.

Long-Term Security Practices

Regularly update software and libraries to the latest versions to patch known vulnerabilities.
Implement network and system monitoring to detect and respond to abnormal resource usage.

Patching and Updates

Apply patches provided by Expat library to address the vulnerability.
Stay informed about security advisories and updates from relevant vendors.