USN-4559-1

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Source
https://ubuntu.com/security/notices/USN-4559-1
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4559-1.json
JSON Data
https://api.test.osv.dev/v1/vulns/USN-4559-1
Upstream
Related
Published
2020-09-30T13:44:33.645901Z
Modified
2025-10-15T16:37:45Z
Summary
samba update
Details

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.

References

Affected packages

Ubuntu:16.04:LTS / samba

Package

Name
samba
Purl
pkg:deb/ubuntu/samba@2:4.3.11+dfsg-0ubuntu0.16.04.31?arch=source&distro=xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2:4.3.11+dfsg-0ubuntu0.16.04.31

Affected versions

2:4.*

2:4.1.17+dfsg-4ubuntu2
2:4.1.20+dfsg-1ubuntu1
2:4.1.20+dfsg-1ubuntu2
2:4.1.20+dfsg-1ubuntu3
2:4.1.20+dfsg-1ubuntu5
2:4.3.3+dfsg-1ubuntu1
2:4.3.3+dfsg-1ubuntu2
2:4.3.3+dfsg-1ubuntu3
2:4.3.6+dfsg-1ubuntu1
2:4.3.8+dfsg-0ubuntu1
2:4.3.9+dfsg-0ubuntu0.16.04.1
2:4.3.9+dfsg-0ubuntu0.16.04.2
2:4.3.9+dfsg-0ubuntu0.16.04.3
2:4.3.11+dfsg-0ubuntu0.16.04.1
2:4.3.11+dfsg-0ubuntu0.16.04.3
2:4.3.11+dfsg-0ubuntu0.16.04.5
2:4.3.11+dfsg-0ubuntu0.16.04.6
2:4.3.11+dfsg-0ubuntu0.16.04.7
2:4.3.11+dfsg-0ubuntu0.16.04.8
2:4.3.11+dfsg-0ubuntu0.16.04.9
2:4.3.11+dfsg-0ubuntu0.16.04.10
2:4.3.11+dfsg-0ubuntu0.16.04.11
2:4.3.11+dfsg-0ubuntu0.16.04.12
2:4.3.11+dfsg-0ubuntu0.16.04.13
2:4.3.11+dfsg-0ubuntu0.16.04.15
2:4.3.11+dfsg-0ubuntu0.16.04.16
2:4.3.11+dfsg-0ubuntu0.16.04.17
2:4.3.11+dfsg-0ubuntu0.16.04.18
2:4.3.11+dfsg-0ubuntu0.16.04.19
2:4.3.11+dfsg-0ubuntu0.16.04.20
2:4.3.11+dfsg-0ubuntu0.16.04.21
2:4.3.11+dfsg-0ubuntu0.16.04.23
2:4.3.11+dfsg-0ubuntu0.16.04.24
2:4.3.11+dfsg-0ubuntu0.16.04.25
2:4.3.11+dfsg-0ubuntu0.16.04.26
2:4.3.11+dfsg-0ubuntu0.16.04.27
2:4.3.11+dfsg-0ubuntu0.16.04.28
2:4.3.11+dfsg-0ubuntu0.16.04.29
2:4.3.11+dfsg-0ubuntu0.16.04.30

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "2:4.3.11+dfsg-0ubuntu0.16.04.31",
            "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"
        }
    ]
}

Database specific

cves_map

{
    "ecosystem": "Ubuntu:16.04:LTS",
    "cves": [
        {
            "id": "CVE-2020-1472",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "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": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}

Ubuntu:18.04:LTS / samba

Package

Name
samba
Purl
pkg:deb/ubuntu/samba@2:4.7.6+dfsg~ubuntu-0ubuntu2.20?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2:4.7.6+dfsg~ubuntu-0ubuntu2.20

Affected versions

2:4.*

2:4.6.7+dfsg-1ubuntu3
2:4.7.1+dfsg-1ubuntu1
2:4.7.3+dfsg-1ubuntu1
2:4.7.4+dfsg-1ubuntu1
2:4.7.6+dfsg~ubuntu-0ubuntu1
2:4.7.6+dfsg~ubuntu-0ubuntu2
2:4.7.6+dfsg~ubuntu-0ubuntu2.2
2:4.7.6+dfsg~ubuntu-0ubuntu2.4
2:4.7.6+dfsg~ubuntu-0ubuntu2.5
2:4.7.6+dfsg~ubuntu-0ubuntu2.6
2:4.7.6+dfsg~ubuntu-0ubuntu2.7
2:4.7.6+dfsg~ubuntu-0ubuntu2.9
2:4.7.6+dfsg~ubuntu-0ubuntu2.10
2:4.7.6+dfsg~ubuntu-0ubuntu2.11
2:4.7.6+dfsg~ubuntu-0ubuntu2.13
2:4.7.6+dfsg~ubuntu-0ubuntu2.14
2:4.7.6+dfsg~ubuntu-0ubuntu2.15
2:4.7.6+dfsg~ubuntu-0ubuntu2.16
2:4.7.6+dfsg~ubuntu-0ubuntu2.17
2:4.7.6+dfsg~ubuntu-0ubuntu2.18
2:4.7.6+dfsg~ubuntu-0ubuntu2.19

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "2:4.7.6+dfsg~ubuntu-0ubuntu2.20",
            "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"
        }
    ]
}

Database specific

cves_map

{
    "ecosystem": "Ubuntu:18.04:LTS",
    "cves": [
        {
            "id": "CVE-2020-1472",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "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": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}

Ubuntu:20.04:LTS / samba

Package

Name
samba
Purl
pkg:deb/ubuntu/samba@2:4.11.6+dfsg-0ubuntu1.5?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2:4.11.6+dfsg-0ubuntu1.5

Affected versions

2:4.*

2:4.10.7+dfsg-0ubuntu2
2:4.10.7+dfsg-0ubuntu3
2:4.11.1+dfsg-3ubuntu1
2:4.11.1+dfsg-3ubuntu2
2:4.11.1+dfsg-3ubuntu4
2:4.11.5+dfsg-1ubuntu1
2:4.11.5+dfsg-1ubuntu2
2:4.11.6+dfsg-0ubuntu1
2:4.11.6+dfsg-0ubuntu1.1
2:4.11.6+dfsg-0ubuntu1.2
2:4.11.6+dfsg-0ubuntu1.3
2:4.11.6+dfsg-0ubuntu1.4

Ecosystem specific 

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "2:4.11.6+dfsg-0ubuntu1.5",
            "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"
        }
    ]
}

Database specific

cves_map

{
    "ecosystem": "Ubuntu:20.04:LTS",
    "cves": [
        {
            "id": "CVE-2020-1472",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "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": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}