[Samba] Can't connect after Ubuntu 18.04.1 Upgrade???

Thomas Rieff trieff at greencaremankato.com
Mon Aug 20 20:02:44 UTC 2018

Thanks for the response... 
per your comments I added the 'ntlm auth = yes" line to smb.conf...bingo bango!!! access was granted. 
Changed win7 " Set the LAN Manager authentication level to NTLMv2 response only/refuse LM and NTLM " 
and then commented out the 'ntlm auth = yes" line to smb.conf , restarted samba and access was granted... 
so my quirk seems to be resolved... 
Thanks for your help. 

If you check the Ubuntu changelog, you will find this:

samba (2:4.7.6+dfsg~ubuntu-0ubuntu2.2) bionic-security; urgency=medium
  * SECURITY UPDATE: Weak authentication protocol allowed
    - debian/patches/CVE-2018-1139-*.patch: Do not allow ntlmv1 over SMB1
      and add tests.
    - CVE-2018-1139

The default setting for ntlm auth is ntlmv2-only, but before the
update, even though it wasn't really allowed by the default setting,
NTLMv1 worked, now it doesn't. I think it is highly likely your
clients are using NTLMv1.
You can easily test this, add 'ntlm auth = yes' to smb.conf and
restart. If this cures your problem, then you have two choices, leave
it alone and put up with a possibly insecure server, or fix your
clients to only use NTLMv2 and remove the line from smb.conf.


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