CVE-2021-40326 Explained : Impact and Mitigation
Learn about CVE-2021-40326, a critical vulnerability in Foxit PDF Reader, PDF Editor, and PhantomPDF versions before 11.1 and 10.1.6. Find out the impacts, affected systems, and mitigation steps.
Foxit PDF Reader and PDF Editor before version 11.1, and PhantomPDF before version 10.1.6, have a vulnerability where signed documents mishandle hidden and incremental data. This flaw allows an attacker to write to arbitrary files and display controlled contents during signature verification.
Understanding CVE-2021-40326
This section provides insights into the impact and technical details of the CVE.
What is CVE-2021-40326?
CVE-2021-40326 is a vulnerability found in Foxit PDF Reader, PDF Editor, and PhantomPDF that enables attackers to manipulate signed documents to write to arbitrary files.
The Impact of CVE-2021-40326
The vulnerability in Foxit PDF software versions allows attackers to execute arbitrary code, compromising the integrity of digitally signed documents.
Technical Details of CVE-2021-40326
Details regarding the vulnerability, affected systems, and exploitation mechanism are discussed in this section.
Vulnerability Description
Foxit PDF Reader and Editor, along with PhantomPDF, fail to handle hidden and incremental data properly in signed documents, leading to unauthorized file writes by attackers.
Affected Systems and Versions
- Affected Products: Foxit PDF Reader, PDF Editor
- Vulnerable Versions: Before 11.1 for Foxit PDF Reader and Editor, before 10.1.6 for PhantomPDF.
Exploitation Mechanism
The vulnerability allows threat actors to write to arbitrary files and display controlled content during the verification of signatures.
Mitigation and Prevention
Preventive measures and actions to mitigate the impact of CVE-2021-40326 are discussed below.
Immediate Steps to Take
- Update Foxit PDF software to the latest versions to patch the vulnerability.
- Avoid opening PDF files from untrusted or unknown sources.
Long-Term Security Practices
- Implement file system whitelisting to restrict unauthorized file writes.
- Regularly update antivirus and security software to detect and prevent such attacks.
Patching and Updates
- Install relevant patches and updates provided by Foxit to address the vulnerability.