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.
{
"binaries": [
{
"binary_name": "ctdb",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "libnss-winbind",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "libpam-winbind",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "libparse-pidl-perl",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "libsmbclient",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "libsmbclient-dev",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "libwbclient-dev",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "libwbclient0",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "python-samba",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "registry-tools",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "samba",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "samba-common",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "samba-common-bin",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "samba-dev",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "samba-dsdb-modules",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "samba-libs",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "samba-testsuite",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "samba-vfs-modules",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "smbclient",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
},
{
"binary_name": "winbind",
"binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31"
}
],
"availability": "No subscription required"
}
{
"ecosystem": "Ubuntu:16.04:LTS",
"cves": [
{
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"id": "CVE-2020-1472"
}
]
}
{
"binaries": [
{
"binary_name": "ctdb",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "libnss-winbind",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "libpam-winbind",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "libparse-pidl-perl",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "libsmbclient",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "libsmbclient-dev",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "libwbclient-dev",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "libwbclient0",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "python-samba",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "registry-tools",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "samba",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "samba-common",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "samba-common-bin",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "samba-dev",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "samba-dsdb-modules",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "samba-libs",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "samba-testsuite",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "samba-vfs-modules",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "smbclient",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
},
{
"binary_name": "winbind",
"binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20"
}
],
"availability": "No subscription required"
}
{
"ecosystem": "Ubuntu:18.04:LTS",
"cves": [
{
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"id": "CVE-2020-1472"
}
]
}
{
"binaries": [
{
"binary_name": "ctdb",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "libnss-winbind",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "libpam-winbind",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "libsmbclient",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "libsmbclient-dev",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "libwbclient-dev",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "libwbclient0",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "python3-samba",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "registry-tools",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "samba",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "samba-common",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "samba-common-bin",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "samba-dev",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "samba-dsdb-modules",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "samba-libs",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "samba-testsuite",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "samba-vfs-modules",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "smbclient",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
},
{
"binary_name": "winbind",
"binary_version": "2:4.11.6+dfsg-0ubuntu1.5"
}
],
"availability": "No subscription required"
}
{
"ecosystem": "Ubuntu:20.04:LTS",
"cves": [
{
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"id": "CVE-2020-1472"
}
]
}