Detection rules › Splunk

AWS High Number Of Failed Authentications From Ip

Status
production
Severity
low
Group by
_time, aws::awsRegion, aws::recipientAccountId, dest, signature, src, vendor_product
Author
Bhavin Patel, Splunk
Source
github.com/splunk/security_content

The following analytic detects an IP address with 20 or more failed authentication attempts to the AWS Web Console within a 5-minute window. This detection leverages CloudTrail logs, aggregating failed login events by IP address and time span. This activity is significant as it may indicate a brute force attack aimed at gaining unauthorized access or escalating privileges within an AWS environment. If confirmed malicious, this could lead to unauthorized access, data breaches, or further exploitation of AWS resources.

MITRE ATT&CK coverage

Rules detecting the same action

Other rules on this platform that filter on the same API call or operation.

Rule body splunk

name: AWS High Number Of Failed Authentications From Ip
id: f75b7f1a-b8eb-4975-a214-ff3e0a944757
version: 11
creation_date: '2023-01-30'
modification_date: '2026-05-13'
author: Bhavin Patel, Splunk
status: production
type: Anomaly
description: The following analytic detects an IP address with 20 or more failed authentication attempts to the AWS Web Console within a 5-minute window. This detection leverages CloudTrail logs, aggregating failed login events by IP address and time span. This activity is significant as it may indicate a brute force attack aimed at gaining unauthorized access or escalating privileges within an AWS environment. If confirmed malicious, this could lead to unauthorized access, data breaches, or further exploitation of AWS resources.
data_source:
    - AWS CloudTrail ConsoleLogin
search: |-
    `cloudtrail` eventName=ConsoleLogin action=failure
      | bucket span=10m _time
      | rename user_name as user
      | stats dc(_raw) AS failed_attempts values(user) as user values(user_agent) as user_agent
        BY _time, src, signature,
           dest, vendor_account vendor_region,
           vendor_product
      | where failed_attempts > 20
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `aws_high_number_of_failed_authentications_from_ip_filter`
how_to_implement: You must install Splunk Add-on for AWS in order to ingest Cloudtrail. We recommend the users to try different combinations of the bucket span time and the tried account threshold to tune this search according to their environment.
known_false_positives: An Ip address with more than 20 failed authentication attempts in the span of 5 minutes may also be triggered by a broken application.
references:
    - https://attack.mitre.org/techniques/T1110/003/
    - https://www.whiteoaksecurity.com/blog/goawsconsolespray-password-spraying-tool/
    - https://softwaresecuritydotblog.wordpress.com/2019/09/28/how-to-protect-against-credential-stuffing-on-aws/
drilldown_searches:
    - name: View the detection results for - "$src$"
      search: '%original_detection_search% | search  src = "$src$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$src$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$src$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
intermediate_findings:
    entities:
        - field: user
          type: user
          score: 20
          message: 'Multiple failed console login attempts (Count: $failed_attempts$) against users from IP Address - $src$'
analytic_story:
    - AWS Identity and Access Management Account Takeover
    - Compromised User Account
asset_type: AWS Account
mitre_attack_id:
    - T1110.003
    - T1110.004
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: cloud
security_domain: threat
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1110.003/aws_mulitple_failed_console_login/aws_cloudtrail.json
          source: aws_cloudtrail
          sourcetype: aws:cloudtrail
      test_type: unit

Stages and Predicates

Stage 1: search

`cloudtrail` eventName=ConsoleLogin action=failure

Stage 2: bucket

| bucket span=10m _time

Stage 3: rename

| rename user_name as user

Stage 4: stats

| stats dc(_raw) AS failed_attempts values(user) as user values(user_agent) as user_agent
    BY _time, src, signature,
       dest, vendor_account vendor_region,
       vendor_product

Stage 5: where

| where failed_attempts > 20

Stage 6: search

| `security_content_ctime(firstTime)`

Stage 7: search

| `security_content_ctime(lastTime)`

Stage 8: search

| `aws_high_number_of_failed_authentications_from_ip_filter`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
actioneq
  • failure
eventNameeq
  • ConsoleLogin
failed_attemptsgt
  • 20
sourcetypeeq
  • aws:cloudtrail