CVE-2021-26272 : Vulnerability Insights and Analysis

A vulnerability was discovered in CKEditor 4 before version 4.16 that allowed for the execution of a ReDoS-type attack by convincing a user to paste specially crafted URL-like text into the editor.

Understanding CVE-2021-26272

This CVE entry describes the details and impact of a security vulnerability present in CKEditor 4.

What is CVE-2021-26272?

The vulnerability in CKEditor 4 before version 4.16 allowed an attacker to perform a ReDoS-type attack by manipulating the Autolink plugin behavior.

The Impact of CVE-2021-26272

By exploiting this vulnerability, an attacker could potentially cause denial of service (DoS) by triggering excessive backtracking in the regular expression engine, leading to a prolonged processing time.

Technical Details of CVE-2021-26272

This section provides more insights into the vulnerability specifics.

Vulnerability Description

The issue arose due to insufficient input validation in the Autolink plugin, enabling an attacker to trick a user into triggering a Regex Denial of Service (ReDoS) attack.

Affected Systems and Versions

All versions of CKEditor 4 before version 4.16 are affected by this vulnerability.

Exploitation Mechanism

To exploit this vulnerability, an attacker would need to craft a malicious URL-like text and persuade a victim to paste it into the CKEditor, then prompt the victim to press Enter or Space.

Mitigation and Prevention

To safeguard against CVE-2021-26272, consider the following security measures.

Immediate Steps to Take

Users should update their CKEditor 4 installations to version 4.16 or newer to mitigate the risk of exploitation.

Long-Term Security Practices

Regularly educate users on safe browsing habits and caution them against pasting untrusted content into editors or similar applications.

Patching and Updates

Stay informed about security patches and update mechanisms provided by the software vendor to ensure timely protection against known vulnerabilities.