Removed required_fields from, well,

everything.

detections/cloud/aws_lambda_updatefunctioncode.yml

@@ -5,12 +5,23 @@ date: '2024-10-22'
 author: Bhavin Patel, Splunk
 status: production
 type: Hunting
-description: The following analytic identifies IAM users attempting to update or modify AWS Lambda code via the AWS CLI. It leverages CloudTrail logs to detect successful `UpdateFunctionCode` events initiated by IAM users. This activity is significant as it may indicate an attempt to gain persistence, further access, or plant backdoors within your AWS environment. If confirmed malicious, an attacker could upload and execute malicious code automatically when the Lambda function is triggered, potentially compromising the integrity and security of your AWS infrastructure.
+description: The following analytic identifies IAM users attempting to update or modify
+  AWS Lambda code via the AWS CLI. It leverages CloudTrail logs to detect successful
+  `UpdateFunctionCode` events initiated by IAM users. This activity is significant
+  as it may indicate an attempt to gain persistence, further access, or plant backdoors
+  within your AWS environment. If confirmed malicious, an attacker could upload and
+  execute malicious code automatically when the Lambda function is triggered, potentially
+  compromising the integrity and security of your AWS infrastructure.
 data_source:
 - AWS CloudTrail
-search: '`cloudtrail` eventSource=lambda.amazonaws.com eventName=UpdateFunctionCode*  errorCode = success  user_type=IAMUser | stats  count min(_time) as firstTime max(_time) as lastTime  values(requestParameters.functionName) as function_updated by src_ip user_arn user_agent user_type eventName aws_account_id |`aws_lambda_updatefunctioncode_filter`'
-how_to_implement: You must install Splunk AWS Add on and enable Cloudtrail logs in your AWS Environment.
-known_false_positives: While this search has no known false positives, it is possible that an AWS admin or an autorized IAM user has updated the lambda fuction code legitimately.
+search: '`cloudtrail` eventSource=lambda.amazonaws.com eventName=UpdateFunctionCode*  errorCode
+  = success  user_type=IAMUser | stats  count min(_time) as firstTime max(_time) as
+  lastTime  values(requestParameters.functionName) as function_updated by src_ip user_arn
+  user_agent user_type eventName aws_account_id |`aws_lambda_updatefunctioncode_filter`'
+how_to_implement: You must install Splunk AWS Add on and enable Cloudtrail logs in
+  your AWS Environment.
+known_false_positives: While this search has no known false positives, it is possible
+  that an AWS admin or an autorized IAM user has updated the lambda fuction code legitimately.
 references:
 - http://detectioninthe.cloud/execution/modify_lambda_function_code/
 - https://sysdig.com/blog/exploit-mitigate-aws-lambdas-mitre/
@@ -20,7 +31,8 @@ tags:
   asset_type: AWS Account
   confidence: 90
   impact: 70
-  message: User $user_arn$ is attempting to update the lambda function code of $function_updated$ from this IP $src_ip$
+  message: User $user_arn$ is attempting to update the lambda function code of $function_updated$
+    from this IP $src_ip$
   mitre_attack_id:
   - T1204
   observable:
@@ -36,15 +48,11 @@ tags:
   - Splunk Enterprise
   - Splunk Enterprise Security
   - Splunk Cloud
-  required_fields:
-  - _time
-  - eventName
-  - userAgent
-  - errorCode
   security_domain: threat
 tests:
 - name: True Positive Test
   attack_data:
-  - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1204/aws_updatelambdafunctioncode/aws_cloudtrail_events.json
+  - data: 
+      https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1204/aws_updatelambdafunctioncode/aws_cloudtrail_events.json
     sourcetype: aws:cloudtrail
     source: aws_cloudtrail