CVE-2021-3964 : Exploit Details and Defense Strategies

This CVE-2021-3964 article provides insights into an Authorization Bypass vulnerability found in elgg/elgg, allowing attackers to bypass authorization through a user-controlled key.

Understanding CVE-2021-3964

This section outlines the impact, technical details, and mitigation strategies related to the CVE-2021-3964 vulnerability.

What is CVE-2021-3964?

elgg/elgg is susceptible to an Authorization Bypass through a user-controlled key, potentially leading to unauthorized access.

The Impact of CVE-2021-3964

The vulnerability poses a medium severity threat with a CVSS base score of 4.3. Attackers with low privileges can exploit this issue over the network.

Technical Details of CVE-2021-3964

This section delves into the specifics of the vulnerability, including its description, affected systems, and exploitation mechanisms.

Vulnerability Description

elgg/elgg versions less than 3.3.22 are affected, allowing unauthorized users to bypass authorization through user-controlled keys.

Affected Systems and Versions

The vulnerability impacts elgg/elgg versions lower than 3.3.22, with a custom version also at risk due to the authorization bypass issue.

Exploitation Mechanism

Attackers can exploit this vulnerability over the network with low complexity, requiring minimal user interaction and privileges.

Mitigation and Prevention

This section provides guidance on immediate steps to take and long-term security practices to mitigate the risks of CVE-2021-3964.

Immediate Steps to Take

Users are advised to update elgg/elgg to version 3.3.22 or higher to address the authorization bypass vulnerability. Additionally, review and restrict user-controlled keys.

Long-Term Security Practices

Implement strong authentication mechanisms, access controls, and regular security assessments to prevent similar authorization bypass issues.

Patching and Updates

Regularly monitor security advisories and apply patches promptly to address known vulnerabilities and enhance the overall security posture of elgg/elgg.