Security Advisory Management

Active Security Considerations

RUSTSEC-2023-0071 - RSA Marvin Attack

Status: Eliminated from Direct Dependencies Advisory: RUSTSEC-2023-0071 Severity: Medium (5.9) Date: 2023-11-22

Vulnerability Description

The Marvin Attack is a potential key recovery attack through timing side-channels that affects RSA decryption operations using private keys.

Current Status

✅ Direct Usage Eliminated (June 2025):

• Removed direct dependency on rsa crate from oauth2-passkey
• Replaced with jsonwebtoken::DecodingKey::from_rsa_components() for JWT verification
• No longer performing any RSA operations in our codebase
• Removed pkcs1 crate dependency used for PEM conversion

Remaining Exposure:

• Transitive dependency through sqlx-mysql → rsa crate
• Pulled in two ways:
  1. SQLx’s macro system (sqlx-macros-core) includes all database drivers at compile time
  2. The mysql feature added in v0.5.0 enables the runtime driver
• Impact: None - the Marvin Attack targets RSA decryption timing to recover a private key, but sqlx-mysql only performs RSA public-key encryption of the password during the MySQL caching_sha2_password authentication handshake. The client never holds an RSA private key, so no decryption oracle exists in this code path
• Risk: Minimal - vulnerability not in our execution path
• CI Status: Advisory ignored (RUSTSEC-2023-0071)

Technical Details:

• Even with MySQL backend selected (GENERIC_DATA_STORE_TYPE=mysql), the client only encrypts outbound credentials with the server’s public key
• Marvin Attack mitigation is the responsibility of the MySQL server (which holds the private key), not the Rust client
• SQLite and PostgreSQL backends do not pull sqlx-mysql at runtime at all

Migration Details

Before (Vulnerable Pattern):

// Used rsa crate directly
let rsa_public_key = RsaPublicKey::new(
    rsa::BigUint::from_bytes_be(&n),
    rsa::BigUint::from_bytes_be(&e),
)?;
let pem = rsa_public_key.to_pkcs1_pem(LineEnding::default())?;
Ok(DecodingKey::from_rsa_pem(pem.as_bytes())?)

After (Secure Pattern):

// Uses jsonwebtoken's built-in RSA support
Ok(DecodingKey::from_rsa_components(n, e)?)

Benefits of Migration

1. Security: Eliminated direct RSA crate usage and vulnerability exposure
2. Simplicity: Reduced code complexity and dependency count
3. Maintenance: Relies on well-maintained jsonwebtoken crate for RSA handling
4. Performance: Eliminated unnecessary base64 decode/encode cycles

Mitigation

• Regular monitoring of RustSec advisories for RSA crate updates
• Consider migration when rsa 0.10+ becomes stable with security fixes
• Current usage pattern remains secure for intended public key operations

Review Schedule

• Next Review: When rsa 0.10.0 stable is released
• Trigger for Action: If vulnerability scope expands to affect public key operations
• Alternative: Monitor for JWT libraries that don’t depend on RSA crate

Last Updated: 2026-05-11 (revised for v0.5.0 MySQL support) Review Frequency: Quarterly or upon new RSA crate releases