Splunk is not a vulnerability scanner. It can index and report on results produced by dedicated vulnerability tools, but doesn't detect vulnerabilities on its own. That's not to say a Splunk query can't find anything with the right data (like, for instance, a running telnetd process) it's just typically not done that way.
If you have a specific vulnerability you need help detecting then post a new question and perhaps someone can help with it.
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If this reply helps you, Karma would be appreciated.
