Modify Lambda Function Code (aws)

Platform	Author	Last Update
aws	Nick Jones	2024-12-02

An attacker may attempt to modify the code that a lambda function executes in order to gain a foothold in the environment

MITRE IDs

• T1059

Required Permissions

• lambda:UpdateFunctionCode

Required Parameters

Name	Type	Description	Example Value
functionname	str	Name of the function to be targeted	example-function
zipfile	str	Filename of the zip file of code to be uploaded	file.zip

Attacker Action

aws lambda update-function-code --function-name example-function --zip-file file.zip --publish

Detection Case

ELK query

When logs are ingested into ELK, the following Lucene query can be used to identify relevant events.

eventName:None AND eventSource:None

Sigma Definition

---
title: Modify Lambda Function Code
id: 7890b11c-19b3-4fb9-bbec-cae87db769ca
status: experimental
author: Nick Jones
date: 2024-12-02
description: An attacker may attempt to modify the code that a lambda function executes in order to gain a foothold in the environment
logsource:
  service: cloudtrail
detection:
  selection_source:
    - eventSource: "None"
  events:
    - eventName: "None"
  condition: selection_source and events
level: low
tags:
  - attack.T1059