{
  "id": 8139603,
  "title": "Stop Hardcoding Your Database Credentials in Lambda — Use IAM Authentication with RDS Proxy Instead",
  "url": "https://urgent.news/2026/09/18/stop-hardcoding-your-database-credentials-in-lambda-use-iam",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-09-18T01:16:47.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/jeancy/stop-hardcoding-your-database-credentials-in-lambda-use-iam-authentication-with-rds-proxy-instead-2a19"
  },
  "original_language": "en",
  "account": "Your Lambda function connects to RDS, queries the database and returns results. In your environment variables, you have a username and password stored in plain text. This approach is not ideal and can be compromised by misconfigurations, accidental log exposures, or leaked deployment artifacts. AWS offers a solution to eliminate database passwords entirely from your Lambda code, improving security and eliminating rotation headaches and secrets leaks. This article explains how to use IAM Authentication with RDS Proxy instead of hardcoding credentials in Lambda.\n\nIAM Authentication with RDS Proxy works by generating a temporary IAM token with a 15-minute validity, which Lambda uses as the database password for the connection. AWS validates the token internally, ensuring that no credentials leave your environment. The process involves creating an IAM role with the rds-db:connect permission, creating a MySQL user that delegates authentication to AWS IAM, configuring RDS Proxy to require IAM Authentication, and attaching the IAM policy to the Lambda role. The Lambda function must be in the same VPC and subnets as the RDS Proxy for the setup to work.\n\nTo enable IAM Authentication on RDS, navigate to RDS → Databases, select your RDS MySQL instance, and modify the settings. Under Database authentication, choose Password and IAM database authentication. To enable IAM Authentication on RDS Proxy, select your Proxy, modify the settings, and under IAM authentication, choose Required. The next step is to create a MySQL user without a password by connecting to your RDS instance, executing a CREATE USER command, and granting SELECT, INSERT, and UPDATE permissions on the desired database. Finally, attach the necessary IAM policy to your Lambda role and configure the Lambda function to run in the same VPC and subnets as the RDS Proxy.",
  "summary": "Your Lambda function works. It connects to RDS, queries the database, returns results. Somewhere in your environment variables sits a username and a password — plain text, sitting there quietly. You know it's not ideal. But it works, so it stays. Here's the thing: one misconfigured IAM policy, one accidental log exposure, one leaked deployment artifact — and those credentials are compromised. AWS…",
  "key_points": [
    "Lambda functions store database credentials in plain text environment variables.",
    "IAM Authentication with RDS Proxy eliminates hardcoding credentials in Lambda.",
    "Enable IAM Authentication on RDS and RDS Proxy, create MySQL user without password."
  ],
  "editors_take": "Switching to IAM Authentication with RDS Proxy eliminates database passwords from Lambda code, improving security and reducing rotation headaches and secrets leaks.",
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}