CVE-2021-41781 Explained : Impact and Mitigation

Foxit PDF Reader before 11.1 and PDF Editor before 11.1, and PhantomPDF before 10.1.6, allow attackers to trigger a use-after-free and execute arbitrary code due to mishandling of JavaScript.

Understanding CVE-2021-41781

Foxit PDF software versions before specified releases are vulnerable to exploitation.

What is CVE-2021-41781?

This CVE identifies a vulnerability in Foxit PDF Reader, PDF Editor, and PhantomPDF that enables attackers to exploit a use-after-free flaw to run arbitrary code through JavaScript manipulation.

The Impact of CVE-2021-41781

Attackers can execute arbitrary code on systems running the affected Foxit products.
Potential compromise of sensitive information stored or accessed via the PDF software.

Technical Details of CVE-2021-41781

The technical aspects of this vulnerability are elaborated below.

Vulnerability Description

The issue lies in the mishandling of JavaScript, specifically in versions prior to Foxit PDF Reader 11.1, PDF Editor 11.1, and PhantomPDF 10.1.6.

Affected Systems and Versions

Products: Foxit PDF Reader, PDF Editor, PhantomPDF
Versions: Before 11.1 (PDF Reader/Editor) and 10.1.6 (PhantomPDF)

Exploitation Mechanism

Attackers exploit a use-after-free vulnerability through JavaScript manipulation to execute unauthorized code.

Mitigation and Prevention

Protective measures to mitigate the risks posed by CVE-2021-41781.

Immediate Steps to Take

Update Foxit PDF software to versions 11.1 (Reader/Editor) and 10.1.6 (PhantomPDF).
Exercise caution when accessing PDF files from unknown or untrusted sources.

Long-Term Security Practices

Regularly update software to the latest versions to patch known vulnerabilities.
Educate users on safe PDF usage practices to prevent exploitation.

Patching and Updates

Foxit has released updated versions (11.1 for Reader/Editor and 10.1.6 for PhantomPDF) to address the vulnerability.