CVE-2021-37626 Explained : Impact and Mitigation

This CVE-2021-37626 impacts Contao, an open-source CMS allowing attackers to load PHP files via insert tags in the Contao back end, affecting versions between 4.0.0 and 4.11.7. It is crucial to update to versions 4.4.56, 4.9.18, or 4.11.7 to mitigate the vulnerability.

Understanding CVE-2021-37626

CVE-2021-37626 is a code injection vulnerability in Contao that enables threat actors to load PHP files through insert tags in the CMS backend, impacting various versions leading up to 4.11.7.

What is CVE-2021-37626?

CVE-2021-37626 allows untrusted backend users to modify fields displayed on the front end, enabling the inclusion of PHP files via insert tags.

The Impact of CVE-2021-37626

The vulnerability poses a high risk with a CVSS base score of 7.2, impacting confidentiality, integrity, and availability. Attackers can exploit this remotely without user interaction.

Technical Details of CVE-2021-37626

This section outlines the technical aspects of the CVE.

Vulnerability Description

Contao versions between 4.0.0 to 4.11.7 are susceptible to PHP file inclusion via insert tags by untrusted backend users modifying fields shown in the front end.

Affected Systems and Versions

The vulnerability affects Contao versions from 4.0.0 to 4.11.7.

Exploitation Mechanism

Threat actors can exploit this vulnerability by inserting PHP files through insert tags in the Contao backend.

Mitigation and Prevention

To address CVE-2021-37626, immediate action is required to safeguard systems.

Immediate Steps to Take

Update Contao to versions 4.4.56, 4.9.18, or 4.11.7. If updating is not feasible, disable login for untrusted backend users to mitigate the risk.

Long-Term Security Practices

Enforce least privilege access, regularly monitor for unauthorized access, and educate users on secure coding practices.

Patching and Updates

Keep Contao up to date with the latest security patches to address known vulnerabilities and enhance system security.