AWS Exfiltration via DataSync Task
Description
This search looks for potential misuse of an AWS service known as DataSync. This AWS service is used to transfer data between different AWS cloud storage services, such as Amazon S3, Amazon EFS, and Amazon FSx for Windows File Server. Attackers can create a task in AWS to periodically copy data from a private AWS location to a public location resulting in the compromise of the data.
- Type: TTP
-
Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Last Updated: 2023-04-10
- Author: Bhavin Patel, Splunk
- ID: 05c4b09f-ea28-4c7c-a7aa-a246f665c8a2
Annotations
Kill Chain Phase
- Exploitation
NIST
- DE.CM
CIS20
- CIS 10
CVE
Search
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`cloudtrail` eventName = CreateTask eventSource="datasync.amazonaws.com"
| rename requestParameters.* as *
| stats count min(_time) as firstTime max(_time) as lastTime by src_ip aws_account_id awsRegion eventName destinationLocationArn sourceLocationArn userAgent user_arn userIdentity.principalId errorCode
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `aws_exfiltration_via_datasync_task_filter`
Macros
The SPL above uses the following Macros:
aws_exfiltration_via_datasync_task_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Required fields
List of fields required to use this analytic.
- _time
- eventName
- user_arn
- src_ip
- aws_account_id
- destinationLocationArn
- sourceLocationArn
- userAgent
- userIdentity.principalId
How To Implement
You must install splunk AWS add on and Splunk App for AWS. This search works with AWS CloudTrail logs.
Known False Positives
It is possible that an AWS Administrator has legitimately created this task for creating backup. Please check the sourceLocationArn
and destinationLocationArn
of this task
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
64.0 | 80 | 80 | DataSync task created on account id - $aws_account_id$ by user $user_arn$ from src_ip $src_ip$ |
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
Reference
- https://labs.nettitude.com/blog/how-to-exfiltrate-aws-ec2-data/
- https://www.shehackske.com/how-to/data-exfiltration-on-cloud-1606/
Test Dataset
Replay any dataset to Splunk Enterprise by using our replay.py
tool or the UI.
Alternatively you can replay a dataset into a Splunk Attack Range
source | version: 1