CVE-2019-20925 : What You Need to Know

A potential vulnerability exists in MongoDB Server versions prior to 4.2.1, 4.0.13, 3.6.15, and 3.4.24, allowing an unauthorized client to launch a denial of service attack through specially crafted wire protocol messages.

Understanding CVE-2019-20925

This CVE involves a denial of service risk due to memory allocation issues triggered by malformed network packets.

What is CVE-2019-20925?

The vulnerability allows unauthorized clients to exploit MongoDB Server by sending specific wire protocol messages, leading to memory allocation errors.

The Impact of CVE-2019-20925

CVSS Base Score: 7.5 (High Severity)
Attack Vector: Network
Availability Impact: High
Attack Complexity: Low
CWE ID: CWE-839: Numeric Range Comparison Without Minimum Check

Technical Details of CVE-2019-20925

This section provides detailed technical insights into the vulnerability.

Vulnerability Description

The flaw enables unauthorized clients to trigger denial of service attacks by sending specially crafted wire protocol messages, causing incorrect memory allocation by the message decompressor.

Affected Systems and Versions

The vulnerability impacts MongoDB Server versions earlier than:

4.2.1 for v4.2
4.0.13 for v4.0
3.6.15 for v3.6
3.4.24 for v3.4

Exploitation Mechanism

Unauthorized clients can exploit the vulnerability by sending specifically designed wire protocol messages that lead to incorrect memory allocation by the message decompressor.

Mitigation and Prevention

Protecting systems from CVE-2019-20925 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update MongoDB Server to versions 4.2.1, 4.0.13, 3.6.15, or 3.4.24 to mitigate the vulnerability.
Monitor network traffic for any suspicious activities.

Long-Term Security Practices

Implement network segmentation to isolate critical systems.
Regularly review and update security configurations.

Patching and Updates

Apply security patches provided by MongoDB Inc. promptly to address the vulnerability.