Security/Guidelines/Key Management
The goal of this document is to help operational teams with the handling and management of cryptographic material. All Mozilla sites and deployment should follow the recommendations below. The Operations Security (OpSec) team maintains this document as a reference guide for operational teams.
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Data Classification
Key material
Key material identifies the cryptographic secrets that compose a key. All key material must be treated as restricted data, meaning that only individual with specific training and need-to-know should have access to key material. Key material must be encrypted on transmission. Key material can be stored in clear text, but with proper access control.
Public certificates
Public certificates are public and do not require specific access control or encryption.
Algorithms by security levels
This section organizes algorithms and key sizes for a given validity period that represent the level of security provided. While 10 years validity may be a requirement for very static keys, such as Root CAs, we do recommend preferring 2 years keys and implementing reliable key rotation, instead of trying to keep key material for long periods of time.
10 years
| Type | Algorithm and key size | Bits of security |
|---|---|---|
| Asymmetric encryption | RSA 4096 bits | 144 bits |
| Asymmetric encryption | ECDSA 384 bits | 192 bits |
| Symmetric encryption | AES-GCM 256 bits | 256 bits |
| Hash & HMAC | SHA-384 | 192 bits |
| Hash & HMAC | SHA3-384 | 192 bits |
2 years
| Type | Algorithm and key size | Bits of security |
|---|---|---|
| Asymmetric keys | RSA 2048 bits | 112 bits |
| Asymmetric keys | ECDSA 224 or 256 bits | 112 bits |
| Symmetric encryption | AES-CBC 128 bits | 128 bits |
| Hash & HMAC | SHA-256 | 128 bits |
| Hash & HMAC | SHA3-256 | 128 bits |
Legacy, not recommended
The following algorithms and sizes are still widely used but do not provide sufficient security for modern services and should be deprecated as soon as possible, unless backward compatibility is a requirement.
| Type | Algorithm and key size | Bits of security |
|---|---|---|
| Asymmetric encryption | RSA 1024 bits and below | 80 bits |
| Asymmetric encryption | ECDSA 160 bits and below | 80 bits |
| Symmetric encryption | 3DES | |
| Symmetric encryption | RC4 | |
| Hash & HMAC | SHA-1 | 80 bits |
| Hash & HMAC | MD5 | 64 bits |