The ipapwd_chpwop function in daemons/ipa-slapi-plugins/ipa-pwd-extop/ipa_pwd_extop.c in the directory server (dirsrv) in FreeIPA before 3.2.0 allows remote attackers to cause a denial of service (crash) via a connection request without a username/dn, related to the 389 directory server.
The client in FreeIPA 2.x and 3.x before 3.1.2 does not properly obtain the Certification Authority (CA) certificate from the server, which allows man-in-the-middle attackers to spoof a join procedure via a crafted certificate.