USN-4721-1

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Source
https://ubuntu.com/security/notices/USN-4721-1
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4721-1.json
JSON Data
https://api.osv.dev/v1/vulns/USN-4721-1
Upstream
Related
Published
2021-02-04T19:45:36.408197Z
Modified
2025-10-13T04:35:20Z
Summary
flatpak vulnerability
Details

Simon McVittie discovered that flatpak-portal service allowed sandboxed applications to execute arbitrary code on the host system (a sandbox escape). A malicious user could create a Flatpak application that set environment variables, trusted by the Flatpak "run" command, and use it to execute arbitrary code outside the sandbox.

References

Affected packages

Ubuntu:18.04:LTS / flatpak

Package

Name
flatpak
Purl
pkg:deb/ubuntu/flatpak@1.0.9-0ubuntu0.2?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.0.9-0ubuntu0.2

Affected versions

0.*

0.8.7-5
0.10.0-1
0.10.0-2
0.10.1-1
0.10.2-1
0.10.2.1-1
0.10.2.1-2
0.10.3-1
0.11.1-0ubuntu1
0.11.3-2
0.11.3-3
0.11.7-0ubuntu0.1

1.*

1.0.1-0ubuntu0.1
1.0.6-0ubuntu0.1
1.0.7-0ubuntu0.18.04.1
1.0.8-0ubuntu0.18.04.1
1.0.9-0ubuntu0.1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "1.0.9-0ubuntu0.2",
            "binary_name": "flatpak"
        },
        {
            "binary_version": "1.0.9-0ubuntu0.2",
            "binary_name": "flatpak-tests"
        },
        {
            "binary_version": "1.0.9-0ubuntu0.2",
            "binary_name": "gir1.2-flatpak-1.0"
        },
        {
            "binary_version": "1.0.9-0ubuntu0.2",
            "binary_name": "libflatpak-dev"
        },
        {
            "binary_version": "1.0.9-0ubuntu0.2",
            "binary_name": "libflatpak0"
        }
    ],
    "availability": "No subscription required"
}

Database specific 

{
    "cves_map": {
        "cves": [
            {
                "severity": [
                    {
                        "score": "CVSS:3.1/AV:L/AC:L/PR:L/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:C/C:H/I:L/A:N",
                        "type": "CVSS_V3"
                    },
                    {
                        "score": "medium",
                        "type": "Ubuntu"
                    }
                ],
                "id": "CVE-2021-21261"
            }
        ],
        "ecosystem": "Ubuntu:18.04:LTS"
    }
}

Ubuntu:20.04:LTS / flatpak

Package

Name
flatpak
Purl
pkg:deb/ubuntu/flatpak@1.6.5-0ubuntu0.2?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.6.5-0ubuntu0.2

Affected versions

1.*

1.4.3-1
1.6.0-1
1.6.1-1
1.6.2-1
1.6.3-1
1.6.5-0ubuntu0.1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_version": "1.6.5-0ubuntu0.2",
            "binary_name": "flatpak"
        },
        {
            "binary_version": "1.6.5-0ubuntu0.2",
            "binary_name": "flatpak-tests"
        },
        {
            "binary_version": "1.6.5-0ubuntu0.2",
            "binary_name": "gir1.2-flatpak-1.0"
        },
        {
            "binary_version": "1.6.5-0ubuntu0.2",
            "binary_name": "libflatpak-dev"
        },
        {
            "binary_version": "1.6.5-0ubuntu0.2",
            "binary_name": "libflatpak0"
        }
    ],
    "availability": "No subscription required"
}

Database specific 

{
    "cves_map": {
        "cves": [
            {
                "severity": [
                    {
                        "score": "CVSS:3.1/AV:L/AC:L/PR:L/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:C/C:H/I:L/A:N",
                        "type": "CVSS_V3"
                    },
                    {
                        "score": "medium",
                        "type": "Ubuntu"
                    }
                ],
                "id": "CVE-2021-21261"
            }
        ],
        "ecosystem": "Ubuntu:20.04:LTS"
    }
}