CVE-2021-39829 : Exploit Details and Defense Strategies

Adobe FrameMaker versions 2019 Update 8 and earlier, and 2020 Release Update 2 and earlier, are impacted by an out-of-bounds write vulnerability potentially leading to arbitrary code execution.

Understanding CVE-2021-39829

Adobe FrameMaker PDF File Parsing Out-of-Bounds Write Remote Code Execution Vulnerability

What is CVE-2021-39829?

Adobe FrameMaker versions 2019 Update 8 and earlier, and 2020 Release Update 2 and earlier, are vulnerable to an out-of-bounds write issue. This vulnerability could allow an attacker to execute arbitrary code within the context of the current user. Exploiting this vulnerability requires user interaction, specifically opening a malicious PDF file.

The Impact of CVE-2021-39829

The vulnerability has a CVSS base score of 7.8, categorizing it as a high severity issue. Key impacts include:

Confidentiality, integrity, and availability are all rated as high.
The attack complexity is low, and user interaction is required.
The attack vector is local with no privileges required.

Technical Details of CVE-2021-39829

Adobe FrameMaker versions 2019 Update 8 and earlier, and 2020 Release Update 2 and earlier, are affected by this vulnerability.

Vulnerability Description

The vulnerability, labeled as an out-of-bounds write (CWE-787), could result in arbitrary code execution in the context of the current user through the manipulation of PDF files.

Affected Systems and Versions

Affected Product: FrameMaker
Vendor: Adobe
Versions Impacted:
FrameMaker 2020.2 and earlier
FrameMaker 2019.8 and earlier
Earlier versions not specified

Exploitation Mechanism

To exploit this vulnerability, a victim must open a malicious PDF file, which triggers the out-of-bounds write and potential remote code execution.

Mitigation and Prevention

Steps to address and prevent exploitation of CVE-2021-39829

Immediate Steps to Take

Update Adobe FrameMaker to the latest version available.
Be cautious when opening PDF files from untrusted sources.
Implement security best practices and user awareness training.

Long-Term Security Practices

Regularly update software and apply security patches promptly.
Use reputable security software to detect and block malicious PDF files.

Patching and Updates

Adobe has released security updates to address this vulnerability. Ensure all systems are patched with the latest updates to mitigate the risk of exploitation.