CVE-2021-21379 : Exploit Details and Defense Strategies

A vulnerability in XWiki Platform versions between 11.4.0 and 11.10.11, 12.0.0 and 12.6.3, and 12.7.0 and 12.8-rc-1 allows execution of unauthorized content with the rights of the author of a macro using

{{wikimacrocontent}}

.

Understanding CVE-2021-21379

This CVE describes a security issue in the XWiki Platform that enables the execution of malicious content with elevated privileges.

What is CVE-2021-21379?

XWiki Platform, a generic wiki platform, processes the

{{wikimacrocontent}}

incorrectly, allowing script injections with elevated permissions.

The Impact of CVE-2021-21379

The vulnerability permits the execution of unauthorized scripts under the guise of the macro author's rights, jeopardizing confidentiality and integrity.

Technical Details of CVE-2021-21379

The vulnerability stems from the mishandling of the

{{wikimacrocontent}}

macro, granting unauthorized access to execute scripts with elevated privileges.

Vulnerability Description

XWiki Platform mismanages the

{{wikimacrocontent}}

macro, enabling the execution of malicious scripts with the macro author's permissions.

Affected Systems and Versions

XWiki Platform versions ranging from 11.4.0 to 11.10.11, 12.0.0 to 12.6.3, and 12.7.0 to 12.8-rc-1 are affected by this vulnerability.

Exploitation Mechanism

Attackers can exploit this issue by injecting malicious scripts using the

{{wikimacrocontent}}

macro in affected XWiki Platform versions.

Mitigation and Prevention

To address CVE-2021-21379, immediate actions to take include updating XWiki Platform to the patched versions and disabling the vulnerable macros.

Immediate Steps to Take

Update XWiki Platform to versions 12.6.3, 11.10.11, or 12.8-rc-1 and disable macros to mitigate the risk of unauthorized script execution.

Long-Term Security Practices

Ensure safe content insertion and user authorization practices to prevent unauthorized script execution in XWiki Platform.

Patching and Updates

Regularly apply security patches and updates provided by XWiki to maintain a secure environment.