Key rotation is the process of regularly changing cryptographic keys used to encrypt and decrypt data, authenticate users, or secure communications. This practice enhances security by reducing the risk of compromised keys being exploited for an extended period.
Why it matters:
- Limits exposure: If a key is stolen or leaked, rotating it minimizes the window of opportunity for attackers.
- Compliance: Many regulations (e.g., PCI DSS, HIPAA) require periodic key changes.
- Mitigates risks: Long-lived keys are more vulnerable to brute-force attacks or key derivation vulnerabilities.
How it works:
- Generate a new key (e.g., AES, RSA, or API access keys).
- Distribute the new key securely to systems/users that need it.
- Deprecate the old key after ensuring a smooth transition (e.g., allowing dual-use during a transition period).
Example:
A company using API keys to authenticate mobile apps might rotate these keys every 90 days. When a new key is issued, the old one is revoked, forcing apps to update to the latest key.
In cloud environments (e.g., Tencent Cloud):
- Tencent Cloud KMS (Key Management Service) automates key rotation for symmetric keys, ensuring compliance and reducing manual effort.
- CAM (Cloud Access Management) supports periodic rotation of secret access keys for IAM users.
For databases or storage, rotating encryption keys (e.g., Tencent Cloud CBS encrypted volumes) ensures data remains protected even if a key is compromised.