Description
lettre is a a mailer library for Rust. Starting in version 0.10.1 and prior to version 0.11.22, an inverted-boolean bug in lettre's `boring-tls` integration silently disables TLS hostname verification for callers using the default (strict) configuration. An on-path attacker presenting any chain-valid certificate for any domain can intercept SMTP submission, including PLAIN/LOGIN credentials and message contents, against any lettre user built with the `boring-tls` feature. Other TLS backends (`native-tls`, `rustls`) are unaffected. Version 0.11.22 patches the issue.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| lettre | lettre | >= 0.10.1, < 0.11.22 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| crates.io | lettre | >= 0.10.1, < 0.11.22 | 0.11.22 | GHSA-4pj9-g833-qx53 |