The remote Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS host has packages installed that are affected by a vulnerability as referenced in the USN-4559-1 advisory.

    Tom Tervoort discovered that the Netlogon protocol implemented by Samba incorrectly handled the     authentication scheme. A remote attacker could use this issue to forge an authentication token and steal     the credentials of the domain admin.

    While a previous security update fixed the issue by changing the server schannel setting to default to     yes, instead of auto, which forced a secure netlogon channel, this update provides additional     improvements.

    For compatibility reasons with older devices, Samba now allows specifying an insecure netlogon     configuration per machine. See the following link for examples:
    https://www.samba.org/samba/security/CVE-2020-1472.html

    In addition, this update adds additional server checks for the protocol attack in the client-specified     challenge to provide some protection when 'server schannel = no/auto' and avoid the false-positive results     when running the proof-of-concept exploit.

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

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Ubuntu 16.04 LTS / 18.04 LTS / 20.04 LTS : Samba update (USN-4559-1)

critical Nessus Plugin ID 141112

Version 1.15