USN-4656-1

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Source
https://ubuntu.com/security/notices/USN-4656-1
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4656-1.json
JSON Data
https://api.osv.dev/v1/vulns/USN-4656-1
Upstream
Related
Published
2020-12-01T16:08:56.577936Z
Modified
2025-09-08T16:36:53Z
Summary
xorg-server, xorg-server-hwe-16.04, xorg-server-hwe-18.04 vulnerabilities
Details

Jan-Niklas Sohn discovered that the X.Org X Server XKB extension incorrectly handled certain inputs. A local attacker could possibly use this issue to escalate privileges.

References

Affected packages

Ubuntu:16.04:LTS / xorg-server

Package

Name
xorg-server
Purl
pkg:deb/ubuntu/xorg-server@2:1.18.4-0ubuntu0.11?arch=source&distro=xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2:1.18.4-0ubuntu0.11

Affected versions

2:1.*

2:1.17.2-1ubuntu9
2:1.17.2-1ubuntu10
2:1.17.3-2ubuntu1
2:1.17.3-2ubuntu2
2:1.17.3-2ubuntu3
2:1.17.3-2ubuntu4
2:1.18.1-1ubuntu3
2:1.18.1-1ubuntu4
2:1.18.3-1ubuntu1
2:1.18.3-1ubuntu2
2:1.18.3-1ubuntu2.2
2:1.18.3-1ubuntu2.3
2:1.18.4-0ubuntu0.1
2:1.18.4-0ubuntu0.2
2:1.18.4-0ubuntu0.3
2:1.18.4-0ubuntu0.4
2:1.18.4-0ubuntu0.6
2:1.18.4-0ubuntu0.7
2:1.18.4-0ubuntu0.8
2:1.18.4-0ubuntu0.9
2:1.18.4-0ubuntu0.10

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "xdmx",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xdmx-tools",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xmir",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xnest",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xorg-server-source",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xserver-common",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xserver-xephyr",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xserver-xorg-core",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xserver-xorg-dev",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xserver-xorg-legacy",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xserver-xorg-xmir",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xvfb",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        },
        {
            "binary_name": "xwayland",
            "binary_version": "2:1.18.4-0ubuntu0.11"
        }
    ],
    "availability": "No subscription required"
}

Ubuntu:16.04:LTS / xorg-server-hwe-16.04

Package

Name
xorg-server-hwe-16.04
Purl
pkg:deb/ubuntu/xorg-server-hwe-16.04@2:1.19.6-1ubuntu4.1~16.04.5?arch=source&distro=xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2:1.19.6-1ubuntu4.1~16.04.5

Affected versions

2:1.*

2:1.18.4-1ubuntu6.1~16.04.1
2:1.18.4-1ubuntu6.1~16.04.2
2:1.19.3-1ubuntu1~16.04.2
2:1.19.3-1ubuntu1~16.04.3
2:1.19.3-1ubuntu1~16.04.4
2:1.19.5-0ubuntu2~16.04.1
2:1.19.6-1ubuntu4~16.04.1
2:1.19.6-1ubuntu4.1~16.04.1
2:1.19.6-1ubuntu4.1~16.04.2
2:1.19.6-1ubuntu4.1~16.04.3
2:1.19.6-1ubuntu4.1~16.04.4

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "xmir-hwe-16.04",
            "binary_version": "2:1.19.6-1ubuntu4.1~16.04.5"
        },
        {
            "binary_name": "xorg-server-source-hwe-16.04",
            "binary_version": "2:1.19.6-1ubuntu4.1~16.04.5"
        },
        {
            "binary_name": "xserver-xephyr-hwe-16.04",
            "binary_version": "2:1.19.6-1ubuntu4.1~16.04.5"
        },
        {
            "binary_name": "xserver-xorg-core-hwe-16.04",
            "binary_version": "2:1.19.6-1ubuntu4.1~16.04.5"
        },
        {
            "binary_name": "xserver-xorg-dev-hwe-16.04",
            "binary_version": "2:1.19.6-1ubuntu4.1~16.04.5"
        },
        {
            "binary_name": "xserver-xorg-legacy-hwe-16.04",
            "binary_version": "2:1.19.6-1ubuntu4.1~16.04.5"
        },
        {
            "binary_name": "xwayland-hwe-16.04",
            "binary_version": "2:1.19.6-1ubuntu4.1~16.04.5"
        }
    ],
    "availability": "No subscription required"
}

Ubuntu:18.04:LTS / xorg-server

Package

Name
xorg-server
Purl
pkg:deb/ubuntu/xorg-server@2:1.19.6-1ubuntu4.8?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2:1.19.6-1ubuntu4.8

Affected versions

2:1.*

2:1.19.5-0ubuntu2
2:1.19.6-1ubuntu1
2:1.19.6-1ubuntu2
2:1.19.6-1ubuntu3
2:1.19.6-1ubuntu4
2:1.19.6-1ubuntu4.1
2:1.19.6-1ubuntu4.2
2:1.19.6-1ubuntu4.3
2:1.19.6-1ubuntu4.4
2:1.19.6-1ubuntu4.5
2:1.19.6-1ubuntu4.6
2:1.19.6-1ubuntu4.7

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "xdmx",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xdmx-tools",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xmir",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xnest",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xorg-server-source",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xserver-common",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xserver-xephyr",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xserver-xorg-core",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xserver-xorg-dev",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xserver-xorg-legacy",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xserver-xorg-xmir",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xvfb",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        },
        {
            "binary_name": "xwayland",
            "binary_version": "2:1.19.6-1ubuntu4.8"
        }
    ],
    "availability": "No subscription required"
}

Ubuntu:18.04:LTS / xorg-server-hwe-18.04

Package

Name
xorg-server-hwe-18.04
Purl
pkg:deb/ubuntu/xorg-server-hwe-18.04@2:1.20.8-2ubuntu2.2~18.04.4?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2:1.20.8-2ubuntu2.2~18.04.4

Affected versions

2:1.*

2:1.20.1-3ubuntu2.1~18.04.1
2:1.20.4-1ubuntu3~18.04.1
2:1.20.5+git20191008-0ubuntu1~18.04.1
2:1.20.8-2ubuntu2.1~18.04.1
2:1.20.8-2ubuntu2.2~18.04.1
2:1.20.8-2ubuntu2.2~18.04.2
2:1.20.8-2ubuntu2.2~18.04.3

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "xorg-server-source-hwe-18.04",
            "binary_version": "2:1.20.8-2ubuntu2.2~18.04.4"
        },
        {
            "binary_name": "xserver-xephyr-hwe-18.04",
            "binary_version": "2:1.20.8-2ubuntu2.2~18.04.4"
        },
        {
            "binary_name": "xserver-xorg-core-hwe-18.04",
            "binary_version": "2:1.20.8-2ubuntu2.2~18.04.4"
        },
        {
            "binary_name": "xserver-xorg-dev-hwe-18.04",
            "binary_version": "2:1.20.8-2ubuntu2.2~18.04.4"
        },
        {
            "binary_name": "xserver-xorg-legacy-hwe-18.04",
            "binary_version": "2:1.20.8-2ubuntu2.2~18.04.4"
        },
        {
            "binary_name": "xwayland-hwe-18.04",
            "binary_version": "2:1.20.8-2ubuntu2.2~18.04.4"
        }
    ],
    "availability": "No subscription required"
}

Ubuntu:20.04:LTS / xorg-server

Package

Name
xorg-server
Purl
pkg:deb/ubuntu/xorg-server@2:1.20.8-2ubuntu2.6?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
2:1.20.8-2ubuntu2.6

Affected versions

2:1.*

2:1.20.5+git20191008-0ubuntu1
2:1.20.6-1ubuntu1
2:1.20.7-2ubuntu1
2:1.20.7-2ubuntu2
2:1.20.8-2ubuntu2
2:1.20.8-2ubuntu2.1
2:1.20.8-2ubuntu2.2
2:1.20.8-2ubuntu2.3
2:1.20.8-2ubuntu2.4

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "xdmx",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xdmx-tools",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xnest",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xorg-server-source",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xserver-common",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xserver-xephyr",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xserver-xorg-core",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xserver-xorg-dev",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xserver-xorg-legacy",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xvfb",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        },
        {
            "binary_name": "xwayland",
            "binary_version": "2:1.20.8-2ubuntu2.6"
        }
    ],
    "availability": "No subscription required"
}