CVE-2025-20322 is a security vulnerability affecting Splunk Enterprise versions prior to 9.4.3, 9.3.5, 9.2.7, and 9.1.10, as well as certain versions of Splunk Cloud Platform below 9.3.2411.104, 9.3.2408.113, and 9.2.2406.119. The vulnerability arises from insufficient verification of whether a request was intentionally submitted by the authenticated user, specifically in the context of executing SPL (Search Processing Language) commands that can trigger a rolling restart of the Search Head Cluster (SHC). This flaw enables an unauthenticated attacker to craft a malicious SPL search command that, if executed by an administrator-level user via their browser, can cause a rolling restart of the SHC. This restart disrupts the availability of search services, effectively resulting in a denial of service (DoS) condition. The attack vector is a Cross-Site Request Forgery (CSRF), which requires the attacker to trick an administrator into initiating the malicious request, typically through phishing or social engineering. The vulnerability does not allow the attacker to exploit the system directly without user interaction and does not impact confidentiality or integrity, but it affects availability by causing service interruptions. The CVSS v3.1 base score is 4.3 (medium severity), reflecting the network attack vector, low complexity, no privileges required, but requiring user interaction, and limited impact to availability only. The rolling restart mechanism is a legitimate administrative function designed to sequentially restart search heads to apply configuration changes or updates without full cluster downtime, but this vulnerability allows it to be triggered maliciously. No known exploits are reported in the wild as of the publication date. The vulnerability underscores the importance of CSRF protections in web applications, especially those with administrative interfaces that can impact service availability.

For European organizations using vulnerable versions of Splunk Enterprise or Splunk Cloud Platform, this vulnerability poses a risk primarily to service availability. Splunk is widely used for security information and event management (SIEM), operational intelligence, and log analysis. A rolling restart triggered unexpectedly can disrupt monitoring and incident response capabilities, potentially delaying detection of real security incidents or operational issues. This could have downstream effects on compliance with regulations such as GDPR, where timely detection and response to data breaches are critical. Additionally, organizations with high availability requirements or those relying on Splunk for critical infrastructure monitoring may experience operational disruptions. While the vulnerability does not allow data exfiltration or modification, the induced downtime could be exploited as part of a broader attack strategy to mask malicious activities or cause operational chaos. The requirement for phishing an administrator means that organizations with strong user awareness and phishing defenses are less likely to be impacted, but those with less mature security cultures or remote workforces may be more vulnerable. Overall, the impact is moderate but significant in environments where Splunk availability is mission-critical.

1. Upgrade Splunk Enterprise and Splunk Cloud Platform to the fixed versions: 9.4.3 or later, 9.3.5 or later, 9.2.7 or later, and 9.1.10 or later as applicable. This is the most effective mitigation. 2. Implement robust anti-CSRF protections on the Splunk web interface, including the use of anti-CSRF tokens and SameSite cookie attributes to prevent unauthorized cross-origin requests. 3. Enforce strict browser security policies such as Content Security Policy (CSP) and enable multi-factor authentication (MFA) for administrator accounts to reduce the risk of phishing success. 4. Conduct targeted phishing awareness training for administrators and privileged users to reduce the likelihood of social engineering exploitation. 5. Monitor Splunk logs and network traffic for unusual SPL search commands or unexpected rolling restart events to detect potential exploitation attempts early. 6. Restrict administrative access to Splunk web interfaces to trusted networks or VPNs to reduce exposure to external attackers. 7. Regularly review and minimize the number of users with administrator privileges to reduce the attack surface. 8. Consider implementing web application firewalls (WAFs) with custom rules to detect and block suspicious SPL commands or CSRF attempts targeting Splunk.