FreeBSD: VID-3d915d96-0b1f-11ec-8d9f-080027415d17 (CVE-2021-33582): cyrus-imapd -- multiple-minute daemon hang via input that is mishandled during hash-table interaction

Cyrus IMAP 3.4.2 Release Notes states: Fixed CVE-2021-33582: Certain user inputs are used as hash table keys during processing. A poorly chosen string hashing algorithm meant that the user could control which bucket their data was stored in, allowing a malicious user to direct many inputs to a single bucket. Each subsequent insertion to the same bucket requires a strcmp of every other entry in it. At tens of thousands of entries, each new insertion could keep the CPU busy in a strcmp loop for minutes. The string hashing algorithm has been replaced with a better one, and now also uses a random seed per hash table, so malicious inputs cannot be precomputed.