UBUNTU-CVE-2021-3520 (CVE-2021-3520)

Vulnerability from osv_ubuntu – Published: 2021-04-30 00:00 – Updated: 2026-04-22 07:39 – Source website
VLAI
Details

There's a flaw in lz4. An attacker who submits a crafted file to an application linked with lz4 may be able to trigger an integer overflow, leading to calling of memmove() on a negative size argument, causing an out-of-bounds write and/or a crash. The greatest impact of this flaw is to availability, with some potential impact to confidentiality and integrity as well.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "liblz4-1",
            "binary_version": "0.0~r114-2ubuntu1+esm2"
          },
          {
            "binary_name": "liblz4-tool",
            "binary_version": "0.0~r114-2ubuntu1+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "lz4",
        "purl": "pkg:deb/ubuntu/lz4@0.0~r114-2ubuntu1+esm2?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.0~r114-2ubuntu1+esm2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.0~r94-2",
        "0.0~r99-1",
        "0.0~r107-1",
        "0.0~r109-1",
        "0.0~r114-2ubuntu1",
        "0.0~r114-2ubuntu1+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "liblz4-1",
            "binary_version": "0.0~r131-2ubuntu2+esm1"
          },
          {
            "binary_name": "liblz4-tool",
            "binary_version": "0.0~r131-2ubuntu2+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "lz4",
        "purl": "pkg:deb/ubuntu/lz4@0.0~r131-2ubuntu2+esm1?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.0~r131-2ubuntu2+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.0~r131-1",
        "0.0~r131-2",
        "0.0~r131-2ubuntu2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "liblz4-1",
            "binary_version": "0.0~r131-2ubuntu3.1"
          },
          {
            "binary_name": "liblz4-tool",
            "binary_version": "0.0~r131-2ubuntu3.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "lz4",
        "purl": "pkg:deb/ubuntu/lz4@0.0~r131-2ubuntu3.1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.0~r131-2ubuntu3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.0~r131-2ubuntu2",
        "0.0~r131-2ubuntu3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "liblz4-1",
            "binary_version": "1.9.2-2ubuntu0.20.04.1"
          },
          {
            "binary_name": "liblz4-tool",
            "binary_version": "1.9.2-2ubuntu0.20.04.1"
          },
          {
            "binary_name": "lz4",
            "binary_version": "1.9.2-2ubuntu0.20.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "lz4",
        "purl": "pkg:deb/ubuntu/lz4@1.9.2-2ubuntu0.20.04.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.9.2-2ubuntu0.20.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.9.1-1",
        "1.9.1-2",
        "1.9.2-2"
      ]
    }
  ],
  "aliases": [],
  "details": "There\u0027s a flaw in lz4. An attacker who submits a crafted file to an application linked with lz4 may be able to trigger an integer overflow, leading to calling of memmove() on a negative size argument, causing an out-of-bounds write and/or a crash. The greatest impact of this flaw is to availability, with some potential impact to confidentiality and integrity as well.",
  "id": "UBUNTU-CVE-2021-3520",
  "modified": "2026-04-22T07:39:46Z",
  "published": "2021-04-30T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-3520"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/lz4/lz4/pull/972"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4968-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4968-2"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-3520"
    }
  ],
  "related": [
    "USN-4968-1",
    "USN-4968-2"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-3520"
  ]
}



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