CVE-2021-33845 : What You Need to Know

A detailed analysis of CVE-2021-33845, a vulnerability in Splunk Enterprise before version 8.1.7 that allows enumeration of usernames through the lockout error message.

Understanding CVE-2021-33845

This section delves into the impact, technical details, and mitigation strategies related to the CVE-2021-33845 vulnerability in Splunk Enterprise.

What is CVE-2021-33845?

The Splunk Enterprise REST API vulnerability enables the enumeration of usernames by exploiting the lockout error message. This issue affects Splunk Enterprise versions prior to 8.1.7 when configured to suppress verbose login errors.

The Impact of CVE-2021-33845

The potential risk associated with CVE-2021-33845 is medium, with a CVSS base score of 5.3. It poses a low confidentiality impact and no integrity or availability impact. The attack complexity is low, and user interaction is not required.

Technical Details of CVE-2021-33845

This section provides an overview of the vulnerability description, affected systems, and the exploitation mechanism.

Vulnerability Description

The vulnerability in the Splunk Enterprise REST API enables malicious actors to enumerate usernames through the lockout error message, compromising user information.

Affected Systems and Versions

Splunk Enterprise versions prior to 8.1.7 are impacted by this vulnerability when the system is set up to suppress detailed login error messages.

Exploitation Mechanism

Attackers can exploit this vulnerability by leveraging the lockout error message in the Splunk Enterprise REST API to enumerate usernames without the need for elevated privileges.

Mitigation and Prevention

This section outlines immediate steps to take and long-term security practices to mitigate the risks posed by CVE-2021-33845.

Immediate Steps to Take

Update Splunk Enterprise to version 8.1.7 or later to address this vulnerability.
Ensure that verbose login error messages are not suppressed to prevent information disclosure.

Long-Term Security Practices

Regularly check for security updates and apply patches promptly to safeguard against known vulnerabilities.
Implement proper access controls and authentication mechanisms to prevent unauthorized access to sensitive information.

Patching and Updates

Stay informed about security advisories from Splunk and other sources to stay ahead of potential threats and apply patches as soon as they are available.