Palo Alto Threat signatures from Unusual IP addresses

Original query, unchanged.

let starttime = 7d;
let endtime = 1d;
let timeframe = 1h;
let HistThreshold = 25; 
let CurrThreshold = 10; 
let HistoricalThreats = CommonSecurityLog
| where isnotempty(SourceIP)
| where TimeGenerated between (startofday(ago(starttime))..startofday(ago(endtime)))
| where DeviceVendor =~ "Palo Alto Networks"
| where Activity =~ "THREAT" and SimplifiedDeviceAction =~ "alert" 
| where DeviceEventClassID in ('spyware', 'scan', 'file', 'vulnerability', 'flood', 'packet', 'virus','wildfire', 'wildfire-virus')
| summarize TotalEvents = count(), ThreatTypes = make_set(DeviceEventClassID), DestinationIpList = make_set(DestinationIP), FirstSeen = min(TimeGenerated) , LastSeen = max(TimeGenerated) by SourceIP, DeviceAction, DeviceVendor;
let CurrentHourThreats =  CommonSecurityLog
| where isnotempty(SourceIP)
| where TimeGenerated > ago(timeframe)
| where DeviceVendor =~ "Palo Alto Networks"
| where Activity =~ "THREAT" and SimplifiedDeviceAction =~ "alert" 
| where DeviceEventClassID in ('spyware', 'scan', 'file', 'vulnerability', 'flood', 'packet', 'virus','wildfire', 'wildfire-virus')
| summarize TotalEvents = count(), ThreatTypes = make_set(DeviceEventClassID), DestinationIpList = make_set(DestinationIP), FirstSeen = min(TimeGenerated) , LastSeen = max(TimeGenerated) by SourceIP, DeviceAction, DeviceProduct, DeviceVendor;
CurrentHourThreats 
| where TotalEvents < CurrThreshold
| join kind = leftanti (HistoricalThreats 
| where TotalEvents > HistThreshold) on SourceIP