Hi, I recently noticed the following problem with a 4.15 Kernel on Linux Mint: /etc/fstab has something like this: > //172.31.9.132/share1 /media/cifs/share1 cifs vers=1.0,credentials=/media/cifs/cifsmount.creds.txt 0 1 > //172.31.9.132/share2 /media/cifs/share2 cifs vers=1.0,credentials=/media/cifs/cifsmount.creds.txt 0 1 > //172.31.9.132/share3 /media/cifs/share3 cifs vers=1.0,credentials=/media/cifs/cifsmount.creds.txt 0 1 > //172.31.9.132/share4 /media/cifs/share4 cifs vers=1.0,credentials=/media/cifs/cifsmount.creds.txt 0 1 172.31.9.132 is a Windows Server in a Domain with Samba AD-DCs. The initial mounting works fine, but after some time Samba logs WRONG_PASSWORD and finally ACCOUNT_LOCKED_OUT. From various clients this happens about once per hour! In order to debug this I extended wireshark. wireshark was already able to decrypt NTLMSSP encryption when an NTLMSSP password and/or a keytab is provided. I extended that in order add some useful expert info that shows which NTHASH was used for a given authentication. That is also available with an Schannel encrypted Netr_LogonSamLogon* call. This landed in wiresharks master branch a few days ago. The customers capture didn't show that information, which meant that the client used a wrong password when it got LOGON_FAILURE from the Windows fileserver (because that got WRONG_PASSWORD or ACCOUNT_LOCKED_OUT from the AD-DC). I cross checked that with smbclient and there wireshark showed the correct password was used. This is very strange and I had the idea to just check if maybe an empty string password was used by the client. So I created a keytab with the NTHASH of an empty string. And wireshark showed that this NTHASH was actually used... Has anybody seen this before? We'll retry this with a newer kernel next week... Otherwise any idea how to debug that? metze
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