CVE-2021-28558 : Security Advisory and Response

Adobe Acrobat Reader DC versions 2021.001.20150 and earlier, 2020.001.30020 and earlier, and 2017.011.30194 and earlier are affected by a Heap-based buffer overflow vulnerability in the PDFLibTool component. This vulnerability could allow an unauthenticated attacker to execute arbitrary code in the context of the current user, requiring victim interaction by opening a malicious file.

Understanding CVE-2021-28558

This security vulnerability, assigned CVE-2021-28558, affects Adobe Acrobat Reader, potentially leading to arbitrary code execution.

What is CVE-2021-28558?

Adobe Acrobat Reader is exposed to a heap-based buffer overflow flaw within the PDFLibTool component. Exploitation could allow attackers to execute arbitrary code under the context of the current user, provided the victim interacts with a malicious file.

The Impact of CVE-2021-28558

This vulnerability holds a CVSS v3.0 Base Score of 8.8, classifying it as a high severity issue. The attack complexity is rated as low, with high impacts on confidentiality, integrity, and availability. User interaction is required for successful exploitation.

Technical Details of CVE-2021-28558

The vulnerability stems from a heap-based buffer overflow within Adobe Acrobat Reader's PDFLibTool component.

Vulnerability Description

An attacker could exploit this vulnerability to achieve arbitrary code execution on the victim's system.

Affected Systems and Versions

Adobe Acrobat Reader DC versions 2021.001.20150, 2020.001.30020, and 2017.011.30194 are confirmed to be impacted.

Exploitation Mechanism

Successful exploitation relies on user interaction, where a victim unwittingly opens a specially crafted malicious file.

Mitigation and Prevention

To address CVE-2021-28558, immediate action and long-term security measures are recommended.

Immediate Steps to Take

Users should update Adobe Acrobat Reader to the latest version to mitigate the vulnerability. Exercise caution when opening PDF files from untrusted sources.

Long-Term Security Practices

Regularly update software applications and maintain awareness of security patches. Educate users on safe browsing practices to prevent malicious file executions.

Patching and Updates

Adobe has released security updates addressing the CVE-2021-28558 vulnerability. Users are advised to promptly apply these patches to secure their systems.