CVE-2021-40726 Explained : Impact and Mitigation

This CVE article provides insight into the Adobe Acrobat Reader DC AcroForm Field Use-After-Free Remote Code Execution Vulnerability.

Understanding CVE-2021-40726

This section delves into the details of the CVE-2021-40726 vulnerability affecting Adobe Acrobat Reader DC.

What is CVE-2021-40726?

Acrobat Reader DC versions 2021.005.20060 and earlier, 2020.004.30006 and earlier, and 2017.011.30199 and earlier are exposed to a use-after-free vulnerability during AcroForm field processing, which may lead to arbitrary code execution with user interaction.

The Impact of CVE-2021-40726

The vulnerability has a high severity level with a CVSS base score of 7.8. It requires user interaction to exploit and could result in arbitrary code execution under the current user's context.

Technical Details of CVE-2021-40726

This section outlines the technical aspects of CVE-2021-40726.

Vulnerability Description

The vulnerability is categorized under CWE-416 (Use After Free) and poses a risk of remote code execution by exploiting AcroForm fields in Acrobat Reader DC.

Affected Systems and Versions

Adobe Acrobat Reader DC versions 2021.005.20060 and earlier
Adobe Acrobat Reader DC versions 2020.004.30006 and earlier
Adobe Acrobat Reader DC versions 2017.011.30199 and earlier
Version 'None'

Exploitation Mechanism

The vulnerability requires user interaction, where the victim must access a malicious page or open a corrupted file to trigger the exploit.

Mitigation and Prevention

Insights on mitigating and preventing the CVE-2021-40726 vulnerability.

Immediate Steps to Take

Update Adobe Acrobat Reader DC to the latest patched version
Exercise caution when opening unfamiliar or suspicious files
Consider using alternative PDF readers temporarily

Long-Term Security Practices

Regularly update software and enable automatic updates where possible
Implement security awareness training to educate users on identifying phishing attempts
Enhance network security with firewalls, intrusion detection systems, and antivirus software

Patching and Updates

Ensure timely installation of security patches provided by Adobe to address the vulnerability.