An issue was discovered in Ruby through 2.6.7, 2.7.x through 2.7.3, and 3.x through 3.0.1. Net::IMAP does not raise an exception when StartTLS fails with an an unknown response, which might allow man-in-the-middle attackers to bypass the TLS protections by leveraging a network position between the client and the registry to block the StartTLS command, aka a StartTLS stripping attack.
The product does not handle or incorrectly handles an exceptional condition.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Ruby | Ruby-lang | 2.6.0 (including) | 2.6.7 (including) |
| Ruby | Ruby-lang | 2.7.0 (including) | 2.7.3 (including) |
| Ruby | Ruby-lang | 3.0.0 (including) | 3.0.1 (including) |