High · published May 10, 2026
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAP#starttls to return "successfully", without starting TLS. This issue has been patched in versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4.
| Product | Versions | Fixed in |
|---|---|---|
| ruby-lang/net\ | < 0.3.10 | 0.3.10 |
| ruby-lang/net\ | ≥ 0.4.0, < 0.4.24 | 0.4.24 |
| ruby-lang/net\ | ≥ 0.5.0, < 0.5.14 | 0.5.14 |
| ruby-lang/net\ | ≥ 0.6.0, < 0.6.4 | 0.6.4 |