Splunk RCE via User XSLT — Detection Rule
The following analytic identifies potential remote code execution (RCE) attempts via user-supplied Extensible Stylesheet Language Transformations (XSLT) in Splunk versions 9.1.x. It detects this activity by analyzing `splunkd_ui` logs for specific URI patterns and status codes indicative of XSLT injection attempts. This activity is significant because successful exploitation could allow an attacker to execute arbitrary code on the Splunk server. If confirmed malicious, this could lead to full system compromise, unauthorized data access, and further lateral movement within the network.