CVE-2021-39826 Explained : Impact and Mitigation

Adobe Digital Editions 4.5.11.187646 (and earlier) are affected by an arbitrary command execution vulnerability, allowing authenticated attackers to execute arbitrary commands through maliciously crafted .epub files.

Understanding CVE-2021-39826

Adobe Digital Editions Command Execution Vulnerability was made public on September 14, 2021.

What is CVE-2021-39826?

Adobe Digital Editions 4.5.11.187646 (and earlier) have a vulnerability that can be exploited by authenticated attackers to execute arbitrary commands.
User interaction is required, as the attack vector involves opening a maliciously crafted .epub file.

The Impact of CVE-2021-39826

CVSS Score: 8.6 (High)
Attack Vector: Local
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Changed
Confidentiality, Integrity, and Availability Impact: High
Vulnerability Type: CWE-78 (OS Command Injection)

Technical Details of CVE-2021-39826

The technical details of the vulnerability are as follows:

Vulnerability Description

Adobe Digital Editions 4.5.11.187646 (and earlier) are susceptible to an arbitrary command execution vulnerability.

Affected Systems and Versions

Product: Digital Editions
Vendor: Adobe
Affected Versions:
Digital Editions 4.5.11.187646
Digital Editions versions earlier than 4.5.11.187646

Exploitation Mechanism

An authenticated attacker can exploit this vulnerability by tricking a user into opening a specially crafted .epub file.

Mitigation and Prevention

It is crucial to take immediate steps to mitigate the risk and prevent exploitation.

Immediate Steps to Take

Update Adobe Digital Editions to the latest version.
Avoid opening untrusted .epub files.

Long-Term Security Practices

Regularly update software and apply security patches.
Educate users about the risks of opening files from unknown or untrusted sources.

Patching and Updates

Adobe has likely released patches for this vulnerability. Stay informed about security advisories and apply patches promptly.