{"id":"UBUNTU-CVE-2021-33643","details":"An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of malloc(0) for a variable gnu_longlink, causing an out-of-bounds read.","modified":"2026-04-22T12:55:25.530041Z","published":"2022-08-10T20:15:00Z","related":["USN-7398-1"],"upstream":["CVE-2021-33643"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-33643"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-33643"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2121289"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-7398-1"}],"affected":[{"package":{"name":"libtar","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/libtar@1.2.20-4ubuntu0.1~esm1?arch=source&distro=esm-apps/xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.2.20-4ubuntu0.1~esm1"}]}],"versions":["1.2.20-4"],"ecosystem_specific":{"binaries":[{"binary_version":"1.2.20-4ubuntu0.1~esm1","binary_name":"libtar0"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33643.json"}},{"package":{"name":"libtar","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/libtar@1.2.20-7ubuntu0.1~esm1?arch=source&distro=esm-apps/bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.2.20-7ubuntu0.1~esm1"}]}],"versions":["1.2.20-7"],"ecosystem_specific":{"binaries":[{"binary_version":"1.2.20-7ubuntu0.1~esm1","binary_name":"libtar0"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33643.json"}},{"package":{"name":"libtar","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/libtar@1.2.20-8ubuntu0.20.04.1?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.2.20-8ubuntu0.20.04.1"}]}],"versions":["1.2.20-7","1.2.20-8"],"ecosystem_specific":{"binaries":[{"binary_version":"1.2.20-8ubuntu0.20.04.1","binary_name":"libtar0"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33643.json"}},{"package":{"name":"libtar","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/libtar@1.2.20-8ubuntu0.22.04.1?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.2.20-8ubuntu0.22.04.1"}]}],"versions":["1.2.20-8"],"ecosystem_specific":{"binaries":[{"binary_version":"1.2.20-8ubuntu0.22.04.1","binary_name":"libtar0"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33643.json"}},{"package":{"name":"libtar","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/libtar@1.2.20-8.1ubuntu0.24.04.1?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.2.20-8.1ubuntu0.24.04.1"}]}],"versions":["1.2.20-8","1.2.20-8.1","1.2.20-8.1build1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.2.20-8.1ubuntu0.24.04.1","binary_name":"libtar0t64"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33643.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:N/A:H"},{"type":"Ubuntu","score":"medium"}]}