Lenient hyper header parsing of Content-Length could allow request smuggling

hyper's HTTP header parser accepted, according to RFC 7230, illegal contents inside Content-Length headers.
Due to this, upstream HTTP proxies that ignore the the header may still forward them along if it chooses to ignore the error.

To be vulnerable, hyper must be used as an HTTP/1 server and using an HTTP proxy upstream that ignores the header's contents
but still forwards it. Due to all the factors that must line up, an attack exploiting this vulnerablity is unlikely.

See advisory page for additional details.

net2 crate has been deprecated; use socket2 instead

The net2 crate has been deprecated
and users are encouraged to considered socket2 instead.

See advisory page for additional details.

Integer overflow in hyper's parsing of the Transfer-Encoding header leads to data loss

When decoding chunk sizes that are too large, hyper's code would encounter an integer overflow. Depending on the situation,
this could lead to data loss from an incorrect total size, or in rarer cases, a request smuggling attack.

To be vulnerable, you must be using hyper for any HTTP/1 purpose, including as a client or server, and consumers must send
requests or responses that specify a chunk size greater than 18 exabytes. For a possible request smuggling attack to be possible,
any upstream proxies must accept a chunk size greater than 64 bits.

See advisory page for additional details.