CVE-2025-20325 is a vulnerability affecting Splunk Enterprise versions prior to 9.4.3, 9.3.5, 9.2.7, and 9.1.10, as well as Splunk Cloud Platform versions below 9.3.2411.103, 9.3.2408.113, and 9.2.2406.119. The issue arises when the Splunk Enterprise Search Head Cluster (SHC) is configured with the SHCConfig log channel set to DEBUG level in a clustered deployment. Under these conditions, the software may inadvertently expose the search head cluster secret key (splunk.secret) through log files. This secret key is critical for securing communications and operations within the search head cluster. The exposure of this key could allow an unauthorized actor with access to the log files or administrative access to internal indexes to retrieve sensitive information that should be restricted. However, exploitation requires either local access to the log files or administrative privileges to internal indexes, which by default are limited to users with the admin role. The vulnerability does not require user interaction and does not directly impact integrity or availability but compromises confidentiality of sensitive cluster secrets. The CVSS v3.1 base score is 3.1, indicating a low severity primarily due to the high attack complexity and the need for privileges to exploit. The vulnerability highlights the importance of careful logging configuration and strict role-based access control within Splunk deployments. The issue is documented with references to Splunk’s official guidance on managing roles, deploying search head clusters, and securing passwords across servers. No known exploits are reported in the wild at this time.

For European organizations using affected versions of Splunk Enterprise or Splunk Cloud Platform, this vulnerability poses a confidentiality risk. If an attacker gains local file system access or administrative access to internal indexes, they could extract the search head cluster secret key, potentially undermining the security of the entire search head cluster. This could lead to unauthorized access to cluster communications or facilitate further lateral movement within the environment. Given Splunk’s widespread use in Europe for security information and event management (SIEM), log aggregation, and operational intelligence, exposure of cluster secrets could compromise the integrity of security monitoring and incident response capabilities. Organizations in regulated sectors such as finance, healthcare, and critical infrastructure could face compliance risks if sensitive data is exposed. However, the requirement for elevated privileges or local access limits the likelihood of remote exploitation. The vulnerability does not directly affect system availability or data integrity but weakens the confidentiality of critical cluster secrets, which could be leveraged in more complex attack chains.

European organizations should immediately audit their Splunk Enterprise and Cloud Platform deployments to identify if they are running affected versions and if the SHCConfig log channel is set to DEBUG level in search head clusters. If so, the logging level should be reverted to a less verbose setting to prevent sensitive information from being logged. Access to log files and internal indexes must be strictly controlled and limited to trusted administrator roles only. Organizations should review and tighten role-based access controls (RBAC) within Splunk, ensuring that only necessary personnel have admin-level privileges. Applying the latest patches and updates from Splunk that address this vulnerability is critical once available. Additionally, organizations should monitor logs for unusual access patterns to internal indexes or log files and consider implementing file integrity monitoring on log directories to detect unauthorized access or modifications. Regular security training for administrators on secure configuration and access management in Splunk environments will further reduce risk.