The remote Samba server is affected by an information disclosure vulnerability.
The version of Samba running on the remote host is 4.4.x prior to 4.4.12, 4.5.x prior to 4.5.7, or 4.6.x prior to 4.6.1. It is, therefore, affected by an information disclosure vulnerability due to a race condition between calls to lstat() for symlink checks and calls to open() to read a file. A local attacker can exploit this, by replacing a recently checked path with a symlink, to disclose arbitrary files on the system. Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.
Upgrade to Samba version 4.4.12 / 4.5.7 / 4.6.1 or later. Alternatively, apply the patch or workaround referenced in the vendor advisory.