There currently are no apps for Bit9 on Splunk Base. If you are an existing bit9 customer, I suggest to get in touch with PM at Bit9. We are interested in hearing about your use cases for a splunk app for Bit9.
Bit9 just released an app https://apps.splunk.com/app/1790/ but it's for the v7.2 release that's in "Early Access".
Mandiant has an integration piece that's written for ArcSight. It'll send the logs to Splunk in CEF and you use the CEF TA to normalize them into Splunk. Talk to your Mandiant rep.