Remove duplicate time filter in IP entity analytic rule

Eliminated a redundant 'TimeGenerated >= ago(ioc_lookBack)' filter from the IPEntity_AppServiceHTTPLogs analytic rule and updated the mainTemplate.json accordingly. This change streamlines the query logic for improved clarity and efficiency.

Author: v-sabiraj

Solutions/Threat Intelligence (NEW)/Analytic Rules/IPEntity_AppServiceHTTPLogs.yaml

@@ -33,7 +33,6 @@ query: |
     | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
     // Filter out indicators without relevant IP address fields
     | where TimeGenerated >= ago(ioc_lookBack)
-    | where TimeGenerated >= ago(ioc_lookBack)
     // Filtering out rows where the Confidence Score is less than 50 as they would not have an Alert Priority label. 
     | where Confidence > 50
     // Select the IP entity based on availability of different IP fields

Solutions/Threat Intelligence (NEW)/Package/3.0.12.zip

@@ -5044,7 +5044,7 @@
                 "description": "Identifies a match in AppServiceHTTPLogs from any IP IOC from TI",
                 "displayName": "TI map IP entity to AppServiceHTTPLogs",
                 "enabled": false,
-                "query": "let dt_lookBack = 1h; // Look back 1 hour for AppServiceHTTPLogs\nlet ioc_lookBack = 14d; // Look back 14 days for threat intelligence indicators\n// Fetch threat intelligence indicators related to IP addresses\nlet IP_Indicators = ThreatIntelIndicators\n  //extract key part of kv pair\n  | extend IndicatorType = replace(@\"\\[|\\]|\\\"\"\", \"\", tostring(split(ObservableKey, \":\", 0)))\n  | where IndicatorType in (\"ipv4-addr\", \"ipv6-addr\", \"network-traffic\")\n  | extend NetworkSourceIP = ObservableValue\n  | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)\n  // Filter out indicators without relevant IP address fields\n  | where TimeGenerated >= ago(ioc_lookBack)\n  | where TimeGenerated >= ago(ioc_lookBack)\n  // Filtering out rows where the Confidence Score is less than 50 as they would not have an Alert Priority label. \n  | where Confidence > 50\n  // Select the IP entity based on availability of different IP fields\n  | extend TI_ipEntity = iff(isnotempty(NetworkSourceIP), NetworkSourceIP, NetworkSourceIP)\n  | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)\n  | extend Url = iff(ObservableKey == \"url:value\", ObservableValue, \"\")\n  // Determine Severity based on ConfidenceScore\n  | extend Severity = case(Confidence > 82, \"High\",\n                                Confidence > 74, \"Medium\",\n                                \"Low\")\n  // Exclude local addresses using the ipv4_is_private operator and filtering out specific address prefixes\n  | where ipv4_is_private(TI_ipEntity) == false and  TI_ipEntity !startswith \"fe80\" and TI_ipEntity !startswith \"::\" and TI_ipEntity !startswith \"127.\"\n  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue\n  | where IsActive and (ValidUntil > now() or isempty(ValidUntil));\n  // Perform a join between IP indicators and AppServiceHTTPLogs to identify potential malicious activity\nIP_Indicators\n| project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, NetworkSourceIP, Type, TI_ipEntity, Severity\n  // Use innerunique to keep performance fast and result set low, as we only need one match to indicate potential malicious activity that needs investigation\n  | join kind=innerunique (\n    AppServiceHTTPLogs | where TimeGenerated >= ago(dt_lookBack)\n    | where isnotempty(CIp)\n    | extend WebApp = split(_ResourceId, '/')[8]\n    | extend AppService_TimeGenerated = TimeGenerated // Rename time column for clarity\n  )\n  on $left.TI_ipEntity == $right.CIp\n  // Filter out logs that occurred after the expiration of the corresponding indicator\n  | where AppService_TimeGenerated < ValidUntil\n  // Group the results by IndicatorId and CIp, and keep the log entry with the latest timestamp\n  | summarize AppService_TimeGenerated = arg_max(AppService_TimeGenerated, *) by Id, CIp\n  // Select the desired output fields\n  | extend Description = tostring(parse_json(Data).description)\n  | extend ActivityGroupNames = extract(@\"ActivityGroup:(\\S+)\", 1, tostring(parse_json(Data).labels))\n  | project AppService_TimeGenerated, Description, ActivityGroupNames, Id, ValidUntil, Confidence, TI_ipEntity, CsUsername, WebApp = split(_ResourceId, '/')[8], CIp, CsHost, NetworkSourceIP, _ResourceId, Type, Url\n  // Extract hostname and DNS domain from the CsHost field\n  | extend HostName = tostring(split(CsHost, '.', 0)[0]), DnsDomain = tostring(strcat_array(array_slice(split(CsHost, '.'), 1, -1), '.'))\n  // Rename the timestamp field\n  | extend timestamp = AppService_TimeGenerated\n",
+                "query": "let dt_lookBack = 1h; // Look back 1 hour for AppServiceHTTPLogs\nlet ioc_lookBack = 14d; // Look back 14 days for threat intelligence indicators\n// Fetch threat intelligence indicators related to IP addresses\nlet IP_Indicators = ThreatIntelIndicators\n  //extract key part of kv pair\n  | extend IndicatorType = replace(@\"\\[|\\]|\\\"\"\", \"\", tostring(split(ObservableKey, \":\", 0)))\n  | where IndicatorType in (\"ipv4-addr\", \"ipv6-addr\", \"network-traffic\")\n  | extend NetworkSourceIP = ObservableValue\n  | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)\n  // Filter out indicators without relevant IP address fields\n  | where TimeGenerated >= ago(ioc_lookBack)\n  // Filtering out rows where the Confidence Score is less than 50 as they would not have an Alert Priority label. \n  | where Confidence > 50\n  // Select the IP entity based on availability of different IP fields\n  | extend TI_ipEntity = iff(isnotempty(NetworkSourceIP), NetworkSourceIP, NetworkSourceIP)\n  | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)\n  | extend Url = iff(ObservableKey == \"url:value\", ObservableValue, \"\")\n  // Determine Severity based on ConfidenceScore\n  | extend Severity = case(Confidence > 82, \"High\",\n                                Confidence > 74, \"Medium\",\n                                \"Low\")\n  // Exclude local addresses using the ipv4_is_private operator and filtering out specific address prefixes\n  | where ipv4_is_private(TI_ipEntity) == false and  TI_ipEntity !startswith \"fe80\" and TI_ipEntity !startswith \"::\" and TI_ipEntity !startswith \"127.\"\n  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue\n  | where IsActive and (ValidUntil > now() or isempty(ValidUntil));\n  // Perform a join between IP indicators and AppServiceHTTPLogs to identify potential malicious activity\nIP_Indicators\n| project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, NetworkSourceIP, Type, TI_ipEntity, Severity\n  // Use innerunique to keep performance fast and result set low, as we only need one match to indicate potential malicious activity that needs investigation\n  | join kind=innerunique (\n    AppServiceHTTPLogs | where TimeGenerated >= ago(dt_lookBack)\n    | where isnotempty(CIp)\n    | extend WebApp = split(_ResourceId, '/')[8]\n    | extend AppService_TimeGenerated = TimeGenerated // Rename time column for clarity\n  )\n  on $left.TI_ipEntity == $right.CIp\n  // Filter out logs that occurred after the expiration of the corresponding indicator\n  | where AppService_TimeGenerated < ValidUntil\n  // Group the results by IndicatorId and CIp, and keep the log entry with the latest timestamp\n  | summarize AppService_TimeGenerated = arg_max(AppService_TimeGenerated, *) by Id, CIp\n  // Select the desired output fields\n  | extend Description = tostring(parse_json(Data).description)\n  | extend ActivityGroupNames = extract(@\"ActivityGroup:(\\S+)\", 1, tostring(parse_json(Data).labels))\n  | project AppService_TimeGenerated, Description, ActivityGroupNames, Id, ValidUntil, Confidence, TI_ipEntity, CsUsername, WebApp = split(_ResourceId, '/')[8], CIp, CsHost, NetworkSourceIP, _ResourceId, Type, Url\n  // Extract hostname and DNS domain from the CsHost field\n  | extend HostName = tostring(split(CsHost, '.', 0)[0]), DnsDomain = tostring(strcat_array(array_slice(split(CsHost, '.'), 1, -1), '.'))\n  // Rename the timestamp field\n  | extend timestamp = AppService_TimeGenerated\n",
                 "queryFrequency": "PT1H",
                 "queryPeriod": "P14D",
                 "severity": "Medium",