CVE-2026-22008 – AWS Lambda Layer Injection via Shared Layer ARN

Program Code (Python)

# deploy_vulnerable_lambda.py - Lambda function using a layer from untrusted account
import boto3
lambda_client = boto3.client('lambda')
# Attacker publishes a public layer containing malicious code
# Victim function references the layer ARN
response = lambda_client.create_function(
    FunctionName='victim-func',
    Runtime='python3.9',
    Role='arn:aws:iam::123456789012:role/lambda-role',
    Handler='index.handler',
    Code={'ZipFile': open('function.zip','rb').read()},
    Layers=['arn:aws:lambda:us-east-1:123456789012:layer:poisoned:1']  # public, but owned by attacker
)
print("Function created with malicious layer")

CVE-2026-22008 – AWS Lambda Layer Injection via Untrusted ARN

Overview

An AWS Lambda function includes a Lambda Layer from a publicly shared but untrusted ARN. The layer’s code runs inside the function’s execution environment, allowing the layer publisher to steal credentials, exfiltrate data, and execute arbitrary code.

Vulnerability Details

• Type: Supply Chain / Code Injection
• Impact: Full function compromise, credential theft.
• Root Cause: Lambda layers are merged into the function’s code; no signature verification is required. A malicious layer owner can update the layer and affect all functions using it.

Exploit Demonstration

Deploy the victim function using the vulnerable script (requires AWS sandbox):

python deploy_vulnerable_lambda.py

The layer’s handler is invoked on each request, phoning home.