"net/http: limit canonical header cache by bytes, not entries
An attacker can cause excessive memory growth in a Go server accepting HTTP/2 requests.
HTTP/2 server connections contain a cache of HTTP header keys sent by the client. While the total number of entries in this cache is capped, an attacker sending very large keys can cause the server to allocate approximately 64 MiB per open connection.
This issue is also fixed in golang.org/x/net/http2 vX.Y.Z, for users manually configuring HTTP/2.
Thanks to Josselin Costanzi for reporting this issue.
This is CVE-2022-41717 and Go issue https://go.dev/issue/56350."