CVE-2022-21681 Explained : Impact and Mitigation

Marked, a markdown parser and compiler, prior to version 4.0.10, is susceptible to exponential catastrophic backtracking (ReDoS) due to a regular expression issue. This vulnerability could lead to denial of service (DoS) attacks. Learn more about the impact, technical details, and mitigation steps below.

Understanding CVE-2022-21681

Marked, a markdown parser and compiler, contains a vulnerability that can be exploited for denial of service (DoS) attacks.

What is CVE-2022-21681?

CVE-2022-21681 is a vulnerability in Marked prior to version 4.0.10 that allows for exponential catastrophic backtracking (ReDoS) when processing certain strings, potentially leading to a DoS condition.

The Impact of CVE-2022-21681

The vulnerability in Marked could allow an attacker to cause a denial of service (DoS) condition by triggering excessive resource consumption through specific input strings.

Technical Details of CVE-2022-21681

The following technical details outline the vulnerability in Marked prior to version 4.0.10:

Vulnerability Description

The issue arises from the

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regular expression in Marked, which can lead to catastrophic backtracking against certain input strings.

Affected Systems and Versions

The vulnerability impacts marked versions earlier than 4.0.10.

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting malicious input strings that trigger excessive backtracking in the regular expression engine.

Mitigation and Prevention

To address CVE-2022-21681 and protect systems from potential attacks, consider the following mitigation strategies:

Immediate Steps to Take

Upgrade to marked version 4.0.10 or newer to apply the patch that mitigates this vulnerability. Alternatively, avoid processing untrusted markdown through vulnerable versions of marked.

Long-Term Security Practices

Implement input validation mechanisms and sandboxed environments for processing untrusted content to prevent potential DoS attacks.

Patching and Updates

Regularly check for security updates and patches for the software you use, including marked, to address known vulnerabilities and improve overall security posture.