{"id":"UBUNTU-CVE-2021-3520","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.","modified":"2026-04-22T14:48:45.313365Z","published":"2021-04-30T00:00:00Z","related":["USN-4968-1","USN-4968-2"],"upstream":["CVE-2021-3520"],"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"}],"affected":[{"package":{"name":"lz4","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/lz4@0.0~r114-2ubuntu1+esm2?arch=source&distro=trusty/esm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0~r114-2ubuntu1+esm2"}]}],"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":{"binaries":[{"binary_name":"liblz4-1","binary_version":"0.0~r114-2ubuntu1+esm2"},{"binary_name":"liblz4-tool","binary_version":"0.0~r114-2ubuntu1+esm2"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3520.json"}},{"package":{"name":"lz4","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/lz4@0.0~r131-2ubuntu2+esm1?arch=source&distro=esm-infra/xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0~r131-2ubuntu2+esm1"}]}],"versions":["0.0~r131-1","0.0~r131-2","0.0~r131-2ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_name":"liblz4-1","binary_version":"0.0~r131-2ubuntu2+esm1"},{"binary_name":"liblz4-tool","binary_version":"0.0~r131-2ubuntu2+esm1"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3520.json"}},{"package":{"name":"lz4","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/lz4@0.0~r131-2ubuntu3.1?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0~r131-2ubuntu3.1"}]}],"versions":["0.0~r131-2ubuntu2","0.0~r131-2ubuntu3"],"ecosystem_specific":{"binaries":[{"binary_name":"liblz4-1","binary_version":"0.0~r131-2ubuntu3.1"},{"binary_name":"liblz4-tool","binary_version":"0.0~r131-2ubuntu3.1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3520.json"}},{"package":{"name":"lz4","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/lz4@1.9.2-2ubuntu0.20.04.1?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.9.2-2ubuntu0.20.04.1"}]}],"versions":["1.9.1-1","1.9.1-2","1.9.2-2"],"ecosystem_specific":{"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"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3520.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}