{"id":"UBUNTU-CVE-2021-3518","details":"There's a flaw in libxml2 in versions before 2.9.11. An attacker who is able to submit a crafted file to be processed by an application linked with libxml2 could trigger a use-after-free. The greatest impact from this flaw is to confidentiality, integrity, and availability.","modified":"2026-01-30T02:25:54.410084Z","published":"2021-05-18T12:15:00Z","related":["USN-4991-1"],"upstream":["CVE-2021-3518"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-3518"},{"type":"REPORT","url":"https://gitlab.gnome.org/GNOME/libxml2/-/issues/237"},{"type":"REPORT","url":"https://gitlab.gnome.org/GNOME/libxml2/-/commit/1098c30a040e72a4654968547f415be4e4c40fe7"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4991-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-3518"}],"affected":[{"package":{"name":"libxml2","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/libxml2@2.9.1+dfsg1-3ubuntu4.13+esm2?arch=source&distro=trusty/esm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.9.1+dfsg1-3ubuntu4.13+esm2"}]}],"versions":["2.9.1+dfsg1-3ubuntu2","2.9.1+dfsg1-3ubuntu3","2.9.1+dfsg1-3ubuntu4","2.9.1+dfsg1-3ubuntu4.1","2.9.1+dfsg1-3ubuntu4.2","2.9.1+dfsg1-3ubuntu4.3","2.9.1+dfsg1-3ubuntu4.4","2.9.1+dfsg1-3ubuntu4.5","2.9.1+dfsg1-3ubuntu4.6","2.9.1+dfsg1-3ubuntu4.7","2.9.1+dfsg1-3ubuntu4.8","2.9.1+dfsg1-3ubuntu4.9","2.9.1+dfsg1-3ubuntu4.10","2.9.1+dfsg1-3ubuntu4.11","2.9.1+dfsg1-3ubuntu4.12","2.9.1+dfsg1-3ubuntu4.13","2.9.1+dfsg1-3ubuntu4.13+esm1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro","binaries":[{"binary_name":"libxml2","binary_version":"2.9.1+dfsg1-3ubuntu4.13+esm2"},{"binary_name":"libxml2-dev","binary_version":"2.9.1+dfsg1-3ubuntu4.13+esm2"},{"binary_name":"libxml2-utils","binary_version":"2.9.1+dfsg1-3ubuntu4.13+esm2"},{"binary_name":"python-libxml2","binary_version":"2.9.1+dfsg1-3ubuntu4.13+esm2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3518.json"}},{"package":{"name":"libxml2","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/libxml2@2.9.3+dfsg1-1ubuntu0.7+esm1?arch=source&distro=esm-infra/xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.9.3+dfsg1-1ubuntu0.7+esm1"}]}],"versions":["2.9.2+zdfsg1-4","2.9.2+zdfsg1-4ubuntu1","2.9.2+zdfsg1-4ubuntu2","2.9.2+zdfsg1-4ubuntu3","2.9.3+dfsg1-1","2.9.3+dfsg1-1ubuntu0.1","2.9.3+dfsg1-1ubuntu0.2","2.9.3+dfsg1-1ubuntu0.3","2.9.3+dfsg1-1ubuntu0.4","2.9.3+dfsg1-1ubuntu0.5","2.9.3+dfsg1-1ubuntu0.6","2.9.3+dfsg1-1ubuntu0.7"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro","binaries":[{"binary_name":"libxml2","binary_version":"2.9.3+dfsg1-1ubuntu0.7+esm1"},{"binary_name":"libxml2-dev","binary_version":"2.9.3+dfsg1-1ubuntu0.7+esm1"},{"binary_name":"libxml2-utils","binary_version":"2.9.3+dfsg1-1ubuntu0.7+esm1"},{"binary_name":"python-libxml2","binary_version":"2.9.3+dfsg1-1ubuntu0.7+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3518.json"}},{"package":{"name":"libxml2","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/libxml2@2.9.4+dfsg1-6.1ubuntu1.4?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.9.4+dfsg1-6.1ubuntu1.4"}]}],"versions":["2.9.4+dfsg1-4ubuntu1","2.9.4+dfsg1-5ubuntu1","2.9.4+dfsg1-5ubuntu2","2.9.4+dfsg1-5.1ubuntu1","2.9.4+dfsg1-5.2ubuntu1","2.9.4+dfsg1-6.1ubuntu1","2.9.4+dfsg1-6.1ubuntu1.2","2.9.4+dfsg1-6.1ubuntu1.3"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libxml2","binary_version":"2.9.4+dfsg1-6.1ubuntu1.4"},{"binary_name":"libxml2-dev","binary_version":"2.9.4+dfsg1-6.1ubuntu1.4"},{"binary_name":"libxml2-utils","binary_version":"2.9.4+dfsg1-6.1ubuntu1.4"},{"binary_name":"python-libxml2","binary_version":"2.9.4+dfsg1-6.1ubuntu1.4"},{"binary_name":"python3-libxml2","binary_version":"2.9.4+dfsg1-6.1ubuntu1.4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3518.json"}},{"package":{"name":"libxml2","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/libxml2@2.9.10+dfsg-5ubuntu0.20.04.1?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.9.10+dfsg-5ubuntu0.20.04.1"}]}],"versions":["2.9.4+dfsg1-7ubuntu3","2.9.4+dfsg1-7ubuntu5","2.9.4+dfsg1-8ubuntu1","2.9.4+dfsg1-8ubuntu2","2.9.4+dfsg1-8ubuntu3","2.9.10+dfsg-1ubuntu3","2.9.10+dfsg-4build1","2.9.10+dfsg-5"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libxml2","binary_version":"2.9.10+dfsg-5ubuntu0.20.04.1"},{"binary_name":"libxml2-dev","binary_version":"2.9.10+dfsg-5ubuntu0.20.04.1"},{"binary_name":"libxml2-utils","binary_version":"2.9.10+dfsg-5ubuntu0.20.04.1"},{"binary_name":"python-libxml2","binary_version":"2.9.10+dfsg-5ubuntu0.20.04.1"},{"binary_name":"python3-libxml2","binary_version":"2.9.10+dfsg-5ubuntu0.20.04.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3518.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}