That sound you hear is Splunk leaking data
The advisory at Full Disclosure explains that the leak happens if an attacker tricks an authenticated user into visiting a malicious Web page.
It only leaks the username, and whether or not that user has enabled remote access; but this would provide enough for an attacker to try follow-up phishing attacks to try and get the user's credentials.
The issue affects Splunk Enterprise versions 6.5.x before 6.5.3, 6.4.x before 6.4.6, 6.3.x before 6.3.10, 6.2.x before 188.8.131.52, 6.1.x before 6.1.13, 6.0.x before 6.0.14, 5.0.x before 5.0.18 and Splunk Light before 6.5.2, and the company has issued patches for all versions. ®