Detection: AWS Repeated CloudWatch Logs Read Operations

Created: 2026-09-21 Last Updated: 2026-09-21 ID: 3f0ba9e1-c6cf-4317-a6bc-c4bcab2b5a06 Author: Maria Jose Erquiaga, Splunk Type: TTP Product: Splunk Enterprise Security

Description

The following analytic detects a high volume of Amazon CloudWatch Logs read operations performed by the same AWS principal and account within a five-minute period. It identifies more than 500 DescribeLogGroups, DescribeLogStreams, DownloadLogEvents, FilterLogEvents, GetLogEvents, or GetQueryResults API calls. This activity may indicate automated discovery or collection of operational, application, or security telemetry from CloudWatch Logs.

Search

 1`cloudtrail`
 2eventSource="logs.amazonaws.com"
 3eventName IN (
 4    "DescribeLogGroups",
 5    "DescribeLogStreams",
 6    "DownloadLogEvents",
 7    "FilterLogEvents",
 8    "GetLogEvents",
 9    "GetQueryResults"
10)
11
12
13| eval user='userIdentity.principalId'
14
15| eval vendor_account=coalesce(
16    vendor_account,
17    recipientAccountId,
18    'userIdentity.accountId'
19)
20
21| eval role_name='userIdentity.sessionContext.sessionIssuer.userName'
22
23| eval signature=coalesce(signature, eventName)
24
25| eval src=coalesce(src, sourceIPAddress)
26
27| eval user_agent=coalesce(user_agent, userAgent)
28
29| eval vendor_region=coalesce(vendor_region, awsRegion)
30
31
32| where isnotnull(user) AND len(trim(user)) > 0
33
34
35| dedup eventID keepempty=true
36
37
38| sort 0 _time
39
40
41| streamstats time_window=5m count AS event_count
42    by user vendor_account
43
44
45| where event_count > 500
46
47
48| stats max(_time) AS lastTime
49        max(event_count) AS event_count
50        min(_time) AS firstTime
51        values(role_name) AS role_name
52        values(signature) AS api_operations
53        values(src) AS src
54        values(user_agent) AS user_agent
55        values(vendor_region) AS vendor_region
56  by user vendor_account
57
58
59| `security_content_ctime(firstTime)`
60
61| `security_content_ctime(lastTime)`
62
63| `aws_repeated_cloudwatch_logs_read_operations_filter`

Data Source

Name	Platform	Sourcetype	Source
AWS CloudTrail	AWS	`'aws:cloudtrail'`	`'aws_cloudtrail'`

Macros Used

Name	Value
cloudtrail	`sourcetype=aws:cloudtrail`
aws_repeated_cloudwatch_logs_read_operations_filter	`search *`

aws_repeated_cloudwatch_logs_read_operations_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1530	Data from Cloud Storage	Collection

Exploitation

DE.CM

CIS 10

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Finding (Notable)	Yes
Rule Title	`%name%`
Rule Description	`%description%`
Notable Event Fields	user, dest
Creates Intermediate Finding (Risk Event)	No

TTP detections generate a Finding (Notable) and may generate Intermediate Findings (Risk Events) for associated entities.

Implementation

You must install Splunk AWS Add on and enable CloudTrail logs in your AWS Environment.

Known False Positives

Automated log analytics, SIEM pipelines, incident-response tooling, backup processes, and administrative troubleshooting may continuously read CloudWatch Logs and generate a high volume of matching operations. The prevalence of this activity has not yet been evaluated against broader customer telemetry. Review the principal, account, source addresses, user agents, Regions, and accessed CloudWatch Logs resources before escalating.

Associated Analytic Story

Data Exfiltration

Finding

Title	Entity Field	Entity Type	Risk Score
The AWS principal [$user$] performed [$event_count$] CloudWatch Logs read operations	user	user	50

Threat Objects

Field	Type
src	ip_address

References

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`aws_cloudtrail`	`aws:cloudtrail`
Integration	✅ Passing	Dataset	`aws_cloudtrail`	`aws:cloudtrail`

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: GitHub |

Version: 1