Ubuntu Security Notice USN-5822-2

Ubuntu Security Notice 5822-2 - USN-5822-1 fixed vulnerabilities in Samba. The update for Ubuntu 20.04 LTS introduced regressions in certain environments. Pending investigation of these regressions, this update temporarily reverts the security fixes. It was discovered that Samba incorrectly handled the bad password count logic. It was discovered that Samba supported weak RC4/HMAC-MD5 in NetLogon Secure Channel. Greg Hudson discovered that Samba incorrectly handled PAC parsing. Joseph Sutton discovered that Samba could be forced to issue rc4-hmac encrypted Kerberos tickets.

bad channel environments fixes investigation issue logic lts md5 netlogon notice pac parsing password rc4 samba security security notice ubuntu update usn vulnerabilities