Several vulnerabilities have been discovered in the dovecot-core email server. CVE-2020-12100 Receiving mail with deeply nested MIME parts leads to resource exhaustion as dovecot-core attempts to parse it. CVE-2020-12673 dovecot-core"s NTLM implementation does not correctly check message buffer size, which leads to a crash when reading past allocation. CVE-2020-12674 dovecot-core"s RPA mechanism implementation accepts zero-length message, which leads to assert-crash later on.