CVE-2020-7929 : Exploit Details and Defense Strategies

A user authorized to perform database queries may trigger denial of service by issuing a specially crafted query containing a type of regex in MongoDB Server versions prior to 3.6.21 and 4.0.20.

Understanding CVE-2020-7929

This CVE involves a vulnerability in MongoDB Server that could lead to denial of service attacks.

What is CVE-2020-7929?

CVE-2020-7929 is a vulnerability in MongoDB Server versions 3.6 and 4.0 that allows a user with query authorization to cause denial of service by using a specially crafted regex query.

The Impact of CVE-2020-7929

The impact of this vulnerability is rated as MEDIUM with a CVSS base score of 6.5. It can result in a high availability impact.

Technical Details of CVE-2020-7929

This section provides more technical insights into the CVE.

Vulnerability Description

The vulnerability arises from a user with query authorization being able to trigger denial of service by utilizing a specially crafted regex query in MongoDB Server.

Affected Systems and Versions

Affected Versions: MongoDB Server 3.6 versions prior to 3.6.21 and MongoDB Server 4.0 versions prior to 4.0.20.

Exploitation Mechanism

The vulnerability can be exploited by a user with query authorization issuing a specially crafted regex query, leading to denial of service.

Mitigation and Prevention

To address CVE-2020-7929, follow these mitigation strategies:

Immediate Steps to Take

Upgrade MongoDB Server to version 3.6.21 or higher for 3.6 series, and version 4.0.20 or higher for 4.0 series.
Monitor and restrict user query authorizations to prevent misuse.

Long-Term Security Practices

Regularly review and update regex query usage policies.
Conduct security training for database users on safe query practices.

Patching and Updates

Stay informed about security updates from MongoDB Inc. and promptly apply patches to mitigate vulnerabilities.