Critical · published August 4, 2026
In Eclipse Jetty, the Digest authentication server-side component uses ISO-8859-1 to encode the password as bytes.
This was done because the initial specification for HTTP did not specify explicitly a charset, and it was assumed to be ISO-8859-1 for historical reasons.
If the password contains characters that cannot be represented in ISO-8859-1, they are silently replaced by `?`. This happens with passwords that contain Chinese, Cyrillic or Greek characters, for example: `αβ123` converts to `??123`.
An attacker can send a request with a digest `Authorization` header crafted with a password made of only `?` characters; the server would match any password of the same length that contains non-ISO-8859-1 characters.
Recent HTTP Digest [RFC-7616](https://datatracker.ietf.org/doc/html/rfc7616) supports a `charset` parameters that defaults to UTF-8 that allows for correct encoding/decoding of passwords.
| Product | Versions | Fixed in |
|---|---|---|
| eclipse/jetty | ≥ 9.4.0, < 9.4.63 | 9.4.63 |
| eclipse/jetty | ≥ 10.0.0, < 10.0.31 | 10.0.31 |
| eclipse/jetty | ≥ 11.0.0, < 11.0.31 | 11.0.31 |
| eclipse/jetty | ≥ 12.0.0, < 12.0.36 | 12.0.36 |
| eclipse/jetty | ≥ 12.1.0, < 12.1.10 | 12.1.10 |