CVE-2021-29047 : Vulnerability Insights and Analysis

The SimpleCaptcha implementation in Liferay Portal 7.3.4, 7.3.5, and Liferay DXP 7.3 before fix pack 1 has a vulnerability that allows remote attackers to repeatedly perform actions protected by a CAPTCHA challenge by reusing the same CAPTCHA answer.

Understanding CVE-2021-29047

This CVE describes a flaw in how the SimpleCaptcha feature is implemented in certain versions of Liferay Portal and Liferay DXP, potentially enabling attackers to bypass CAPTCHA protection.

What is CVE-2021-29047?

The vulnerability in SimpleCaptcha in Liferay Portal and Liferay DXP versions 7.3.4, 7.3.5, and 7.3 allows malicious actors to reuse the same CAPTCHA answer, compromising the security provided by the CAPTCHA challenge.

The Impact of CVE-2021-29047

The impact of this vulnerability is significant as it enables remote attackers to bypass CAPTCHA challenges and perform unauthorized actions by exploiting the flaw in the CAPTCHA answer validation process.

Technical Details of CVE-2021-29047

This section highlights the technical aspects of the CVE.

Vulnerability Description

The vulnerability arises from the failure of the SimpleCaptcha implementation to invalidate CAPTCHA answers after initial use, allowing attackers to reuse the same answer multiple times.

Affected Systems and Versions

Liferay Portal versions 7.3.4, 7.3.5, and Liferay DXP 7.3 before fix pack 1 are impacted by this vulnerability.

Exploitation Mechanism

Remote attackers can exploit this vulnerability by submitting the same CAPTCHA answer multiple times, thereby bypassing the intended security measure.

Mitigation and Prevention

To address CVE-2021-29047, users and organizations can take the following steps:

Immediate Steps to Take

Upgrade Liferay Portal and Liferay DXP to the latest fixed versions to eliminate the vulnerability.
Implement additional security measures to enhance the overall security posture of the systems.

Long-Term Security Practices

Regularly monitor security advisories and update systems promptly when new fixes are released.
Conduct security assessments and penetration testing to identify and remediate vulnerabilities proactively.

Patching and Updates

Ensure all software components, including Liferay Portal and Liferay DXP, are kept up to date with the latest security patches and fixes to prevent exploitation of known vulnerabilities.