AWS CloudTrail: CreateRoute Adds New Network Route to a Route Table

Flags CloudTrail EC2 CreateRoute events indicating a new route was added to an AWS route table.

FreeReviewedSigma · Medium · v5
Product
aws
Service
cloudtrail
Author
jamesc-grafana (SigmaHQ), DRL 1.1
Published
2024-07-11
Updated
2026-07-31
title: "AWS CloudTrail: CreateRoute Adds New Network Route to a Route Table"
id: 0c2395ec-cda5-4a11-a9b6-7217f052fc77
status: test
description: This rule alerts when an EC2 CreateRoute API call is made, indicating that a new network route was added to a route table. Attackers can abuse routing changes to redirect traffic, enable access to otherwise unreachable networks, or impair network visibility. The detection relies on AWS CloudTrail event fields for eventSource ec2.amazonaws.com and eventName CreateRoute.
references:
  - https://www.gorillastack.com/blog/real-time-events/important-aws-cloudtrail-security-events-tracking/
  - https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/aws/cloudtrail/aws_cloudtrail_new_route_added.yml
author: jamesc-grafana, Huntrule Team
date: 2024-07-11
tags:
  - attack.defense-impairment
  - attack.t1686.001
logsource:
  product: aws
  service: cloudtrail
detection:
  selection:
    eventSource: ec2.amazonaws.com
    eventName: CreateRoute
  condition: selection
falsepositives:
  - New VPC Creation requiring setup of a new route table
  - New subnets added requiring routing setup
level: medium
license: DRL-1.1
related:
  - id: c803b2ce-c4a2-4836-beae-b112010390b1
    type: derived