CVE-2024-29945 is a vulnerability affecting Splunk Enterprise versions below 9.2.1, 9.1.4, and 9.0.9, where sensitive authentication tokens can be inadvertently logged during the token validation process. This exposure arises specifically when Splunk Enterprise is running in debug mode or when the JsonWebToken component is configured to log at the DEBUG level. Under these conditions, authentication tokens, which are critical for user session validation and access control, may be written to log files. These logs could then be accessed by attackers who have gained access to the system or logs, providing them with valuable credentials to impersonate users or escalate privileges. The vulnerability requires that either debug mode is enabled or debug-level logging is configured, which typically requires administrative privileges, limiting the ease of exploitation. However, if exploited, the confidentiality, integrity, and availability of the system are all at high risk, as attackers could use the exposed tokens to bypass authentication and manipulate or disrupt Splunk services. No public exploits have been reported yet, but the vulnerability has been assigned a CVSS v3.1 score of 7.2, indicating a high severity. The issue was publicly disclosed on March 27, 2024, and affects multiple recent versions of Splunk Enterprise, a widely used platform for security information and event management (SIEM).

For European organizations, the exposure of authentication tokens in Splunk Enterprise logs can lead to severe security breaches. Attackers who obtain these tokens could impersonate legitimate users, including administrators, leading to unauthorized access to sensitive data and systems. This can compromise the confidentiality of sensitive information, the integrity of log and event data, and the availability of Splunk services critical for security monitoring and incident response. Organizations in sectors such as finance, healthcare, energy, and government, which rely heavily on Splunk for security analytics, could face regulatory penalties under GDPR if personal data is exposed. The breach of authentication tokens also increases the risk of lateral movement within networks, potentially leading to broader compromises. Given Splunk's role in security operations, disruption or manipulation of its data can delay detection and response to other cyber threats, amplifying overall risk.

To mitigate this vulnerability, organizations should immediately upgrade Splunk Enterprise to versions 9.2.1, 9.1.4, or 9.0.9 or later, where the issue is resolved. Until upgrades can be applied, disable debug mode and avoid setting the JsonWebToken component to DEBUG logging level to prevent sensitive token information from being logged. Access to log files should be strictly controlled and monitored, ensuring only authorized personnel can view or modify them. Implement robust logging and monitoring to detect any unauthorized changes to logging configurations or unexpected debug logging activity. Regularly audit Splunk configurations and logs for signs of token exposure or misuse. Additionally, enforce strong access controls and multi-factor authentication for administrative access to Splunk systems to reduce the risk of attackers enabling debug logging. Finally, review and rotate authentication tokens and credentials if exposure is suspected.