Keytab Extraction

Revision as of 08:53, 4 August 2010 by Kai (talk | contribs) (Samba3: Fix keytab extraction instructions.)

How to Extract a keytab containing your domain's passwords

The keytab, a standard format for the storage of Kerberos keys, is also the input required by Wireshark to decrypt encrypted traffic

There are two ways to obtain a keytab from a Windows domain, with Samba:

Samba4

To join the domain, run:

net vampire NETBIOS_DOMAIN_NAME --realm=REALM -Uadministrator

If everything is set up correctly, it should just work. If not, check /etc/krb5.conf in particular - ensure it can reach the KDC by setting:

[libdefaults]
dns_lookup_kdc = true

Then, to extract the keytab run

net export keytab PATH_TO_KEYAB

It will write out a keytab in the path specified, containing the current keys for every host.

Samba3

To dump a keytab, join the domain and then run:

net rpc vampire keytab /path/to/keytab/file

Note that the path to the keytab file needs to be an absolute path.