We have a bug bounty program on Immunefi. Please report any security issues you find through the Immunefi dashboard, or reach out to [email protected].
Critical bug fixes will be backported to past major releases.
The recommendation is to use the latest version available.
| Version | Supported | 
|---|---|
| 4.x | ✅✅ | 
| 3.4 | ✅ | 
| 2.5 | ✅ | 
| < 2.0 | ❌ | 
Note that the Solidity language itself only guarantees security updates for the latest release.