If Thunderbird is configured to use STARTTLS for an IMAP server, and the server sends a PREAUTH response, then Thunderbird will continue with an unencrypted connection, causing email data to be sent without protection. This vulnerability affects Thunderbird < 68.9.0.
| Software | From | Fixed in |
|---|---|---|
| mozilla / thunderbird | - | 68.9.0 |
| canonical / ubuntu_linux | 18.04 | 18.04.x |
| canonical / ubuntu_linux | 19.10 | 19.10.x |
| canonical / ubuntu_linux | 20.04 | 20.04.x |
| canonical / ubuntu_linux | 16.04 | 16.04.x |