CWE-173

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.

A flaw was found in WildFly Elytron. Password hashing and verification normalize input with Unicode NFKC, which can collapse fullwidth characters to ASCII equivalents. A remote attacker can more easily guess affected passwords by using an ASCII-only dictionary against accounts whose passwords were intended to include those non-ASCII characters, leading to unauthorized access.

In JetBrains YouTrack before 2024.3.52635 potential spoofing attack was possible via lack of Punycode encoding

Denial of service could be caused to markdown-it-py, before v2.2.0, if an attacker was allowed to force null assertions with specially crafted input.

Denial of service could be caused to the command line interface of markdown-it-py, before v2.2.0, if an attacker was allowed to use invalid UTF-8 characters as input.