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USN-5292-3 (UBUNTU-CVE-2021-3155)

Vulnerability from osv_ubuntu – Published: 2022-02-18 02:21 – Updated: 2026-06-29 10:52 – Source website
VLAI
Summary
snapd vulnerabilities
Details

USN-5292-1 fixed several vulnerabilities in snapd. This update provides the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.

Original advisory details:

James Troup discovered that snap did not properly manage the permissions for the snap directories. A local attacker could possibly use this issue to expose sensitive information. (CVE-2021-3155)

Ian Johnson discovered that snapd did not properly validate content interfaces and layout paths. A local attacker could possibly use this issue to inject arbitrary AppArmor policy rules, resulting in a bypass of intended access restrictions. (CVE-2021-4120)

The Qualys Research Team discovered that snapd did not properly validate the location of the snap-confine binary. A local attacker could possibly use this issue to execute other arbitrary binaries and escalate privileges. (CVE-2021-44730)

The Qualys Research Team discovered that a race condition existed in the snapd snap-confine binary when preparing a private mount namespace for a snap. A local attacker could possibly use this issue to escalate privileges and execute arbitrary code. (CVE-2021-44731)

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2021-4120",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/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:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-44730",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:H/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:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "high",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-44731",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "high",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:14.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "golang-github-snapcore-snapd-dev",
            "binary_version": "2.54.3+14.04~esm1"
          },
          {
            "binary_name": "golang-github-ubuntu-core-snappy-dev",
            "binary_version": "2.54.3+14.04~esm1"
          },
          {
            "binary_name": "snap-confine",
            "binary_version": "2.54.3+14.04~esm1"
          },
          {
            "binary_name": "snapd",
            "binary_version": "2.54.3+14.04~esm1"
          },
          {
            "binary_name": "snapd-xdg-open",
            "binary_version": "2.54.3+14.04~esm1"
          },
          {
            "binary_name": "ubuntu-core-launcher",
            "binary_version": "2.54.3+14.04~esm1"
          },
          {
            "binary_name": "ubuntu-core-snapd-units",
            "binary_version": "2.54.3+14.04~esm1"
          },
          {
            "binary_name": "ubuntu-snappy",
            "binary_version": "2.54.3+14.04~esm1"
          },
          {
            "binary_name": "ubuntu-snappy-cli",
            "binary_version": "2.54.3+14.04~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "snapd",
        "purl": "pkg:deb/ubuntu/snapd@2.54.3+14.04~esm1?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.54.3+14.04~esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.21~14.04.2",
        "2.22.2~14.04",
        "2.22.3~14.04",
        "2.22.6~14.04",
        "2.23.1~14.04",
        "2.24.1~14.04",
        "2.25~14.04",
        "2.26.10~14.04",
        "2.27.5~14.04",
        "2.28.5~14.04",
        "2.29.4.2~14.04",
        "2.32.3.2~14.04",
        "2.32.9~14.04",
        "2.33.1~14.04",
        "2.34.2~14.04",
        "2.34.2~14.04.1",
        "2.37.4~14.04.1",
        "2.38~14.04"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2021-3155",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-4120",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/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:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-44730",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:H/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:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "high",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2021-44731",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "high",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:16.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "golang-github-snapcore-snapd-dev",
            "binary_version": "2.54.3+16.04~esm2"
          },
          {
            "binary_name": "golang-github-ubuntu-core-snappy-dev",
            "binary_version": "2.54.3+16.04~esm2"
          },
          {
            "binary_name": "snap-confine",
            "binary_version": "2.54.3+16.04~esm2"
          },
          {
            "binary_name": "snapd",
            "binary_version": "2.54.3+16.04~esm2"
          },
          {
            "binary_name": "snapd-xdg-open",
            "binary_version": "2.54.3+16.04~esm2"
          },
          {
            "binary_name": "ubuntu-core-launcher",
            "binary_version": "2.54.3+16.04~esm2"
          },
          {
            "binary_name": "ubuntu-core-snapd-units",
            "binary_version": "2.54.3+16.04~esm2"
          },
          {
            "binary_name": "ubuntu-snappy",
            "binary_version": "2.54.3+16.04~esm2"
          },
          {
            "binary_name": "ubuntu-snappy-cli",
            "binary_version": "2.54.3+16.04~esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "snapd",
        "purl": "pkg:deb/ubuntu/snapd@2.54.3+16.04~esm2?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.54.3+16.04~esm2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.9",
        "1.9.1.1",
        "1.9.2",
        "2.0",
        "2.0.1",
        "2.0.2",
        "2.0.3",
        "2.0.5",
        "2.0.8",
        "2.0.9",
        "2.0.10",
        "2.11+0.16.04",
        "2.12+0.16.04",
        "2.13",
        "2.14.2~16.04",
        "2.15.2ubuntu1",
        "2.16ubuntu3",
        "2.17.1ubuntu1",
        "2.20.1ubuntu1",
        "2.21",
        "2.22.2",
        "2.22.3",
        "2.22.6",
        "2.23.1",
        "2.24.1",
        "2.25",
        "2.26.10",
        "2.27.5",
        "2.28.5",
        "2.29.4.2",
        "2.32.3.2",
        "2.32.9",
        "2.33.1ubuntu2",
        "2.34.2",
        "2.34.2ubuntu0.1",
        "2.37.4",
        "2.37.4ubuntu0.1",
        "2.38",
        "2.39.2",
        "2.39.2ubuntu0.2",
        "2.40",
        "2.42.1",
        "2.45.1",
        "2.45.1ubuntu0.2",
        "2.46.1",
        "2.47.1",
        "2.48",
        "2.48.3"
      ]
    }
  ],
  "aliases": [],
  "details": "USN-5292-1 fixed several vulnerabilities in snapd. This update provides the\ncorresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM.\n\nOriginal advisory details:\n\n James Troup discovered that snap did not properly manage the permissions for\n the snap directories. A local attacker could possibly use this issue to expose\n sensitive information. (CVE-2021-3155)\n \n Ian Johnson discovered that snapd did not properly validate content interfaces\n and layout paths. A local attacker could possibly use this issue to inject\n arbitrary AppArmor policy rules, resulting in a bypass of intended access\n restrictions. (CVE-2021-4120)\n \n The Qualys Research Team discovered that snapd did not properly validate the\n location of the snap-confine binary. A local attacker could possibly use this\n issue to execute other arbitrary binaries and escalate privileges.\n (CVE-2021-44730)\n \n The Qualys Research Team discovered that a race condition existed in the snapd\n snap-confine binary when preparing a private mount namespace for a snap. A\n local attacker could possibly use this issue to escalate privileges and\n execute arbitrary code. (CVE-2021-44731)\n",
  "id": "USN-5292-3",
  "modified": "2026-06-29T10:52:53Z",
  "published": "2022-02-18T02:21:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5292-3"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-3155"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-4120"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-44730"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-44731"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "snapd vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2021-3155",
    "UBUNTU-CVE-2021-4120",
    "UBUNTU-CVE-2021-44730",
    "UBUNTU-CVE-2021-44731"
  ]
}



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