{"id":"UBUNTU-CVE-2021-3975","details":"A use-after-free flaw was found in libvirt. The qemuMonitorUnregister() function in qemuProcessHandleMonitorEOF is called using multiple threads without being adequately protected by a monitor lock. This flaw could be triggered by the virConnectGetAllDomainStats API when the guest is shutting down. An unprivileged client with a read-only connection could use this flaw to perform a denial of service attack by causing the libvirt daemon to crash.","modified":"2026-01-30T02:01:34.831524Z","published":"2021-11-24T00:00:00Z","related":["USN-5399-1"],"upstream":["CVE-2021-3975"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-3975"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5399-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-3975"}],"affected":[{"package":{"name":"libvirt","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/libvirt@1.2.2-0ubuntu13.1.28+esm1?arch=source&distro=esm-infra-legacy/trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.1.1-0ubuntu8","1.1.1-0ubuntu9","1.1.4-0ubuntu2","1.1.4-0ubuntu3","1.1.4-0ubuntu4","1.1.4-0ubuntu5","1.2.0-0ubuntu1","1.2.0-0ubuntu2","1.2.0-0ubuntu3","1.2.1-0ubuntu1","1.2.1-0ubuntu2","1.2.1-0ubuntu3","1.2.1-0ubuntu4","1.2.1-0ubuntu5","1.2.1-0ubuntu7","1.2.1-0ubuntu8","1.2.1-0ubuntu9","1.2.1-0ubuntu10","1.2.2-0ubuntu1","1.2.2-0ubuntu2","1.2.2-0ubuntu3","1.2.2-0ubuntu4","1.2.2-0ubuntu5","1.2.2-0ubuntu6","1.2.2-0ubuntu7","1.2.2-0ubuntu8","1.2.2-0ubuntu9","1.2.2-0ubuntu10","1.2.2-0ubuntu11","1.2.2-0ubuntu12","1.2.2-0ubuntu13","1.2.2-0ubuntu13.1","1.2.2-0ubuntu13.1.1","1.2.2-0ubuntu13.1.2","1.2.2-0ubuntu13.1.4","1.2.2-0ubuntu13.1.5","1.2.2-0ubuntu13.1.6","1.2.2-0ubuntu13.1.7","1.2.2-0ubuntu13.1.8","1.2.2-0ubuntu13.1.9","1.2.2-0ubuntu13.1.10","1.2.2-0ubuntu13.1.12","1.2.2-0ubuntu13.1.14","1.2.2-0ubuntu13.1.16","1.2.2-0ubuntu13.1.17","1.2.2-0ubuntu13.1.20","1.2.2-0ubuntu13.1.21","1.2.2-0ubuntu13.1.22","1.2.2-0ubuntu13.1.23","1.2.2-0ubuntu13.1.25","1.2.2-0ubuntu13.1.26","1.2.2-0ubuntu13.1.27","1.2.2-0ubuntu13.1.28","1.2.2-0ubuntu13.1.28+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libvirt-bin","binary_version":"1.2.2-0ubuntu13.1.28+esm1"},{"binary_name":"libvirt-dev","binary_version":"1.2.2-0ubuntu13.1.28+esm1"},{"binary_name":"libvirt0","binary_version":"1.2.2-0ubuntu13.1.28+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3975.json"}},{"package":{"name":"libvirt","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/libvirt@1.3.1-1ubuntu10.31?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.2.16-2ubuntu11","1.2.16-2ubuntu12","1.2.16-2ubuntu13","1.2.16-2ubuntu14","1.2.21-2ubuntu1","1.2.21-2ubuntu3","1.2.21-2ubuntu4","1.2.21-2ubuntu5","1.2.21-2ubuntu7","1.2.21-2ubuntu8","1.2.21-2ubuntu9","1.2.21-2ubuntu10","1.3.1-1ubuntu1","1.3.1-1ubuntu2","1.3.1-1ubuntu3","1.3.1-1ubuntu4","1.3.1-1ubuntu6","1.3.1-1ubuntu9","1.3.1-1ubuntu10","1.3.1-1ubuntu10.1","1.3.1-1ubuntu10.2","1.3.1-1ubuntu10.3","1.3.1-1ubuntu10.5","1.3.1-1ubuntu10.6","1.3.1-1ubuntu10.7","1.3.1-1ubuntu10.8","1.3.1-1ubuntu10.10","1.3.1-1ubuntu10.11","1.3.1-1ubuntu10.12","1.3.1-1ubuntu10.13","1.3.1-1ubuntu10.14","1.3.1-1ubuntu10.15","1.3.1-1ubuntu10.17","1.3.1-1ubuntu10.18","1.3.1-1ubuntu10.19","1.3.1-1ubuntu10.21","1.3.1-1ubuntu10.22","1.3.1-1ubuntu10.23","1.3.1-1ubuntu10.24","1.3.1-1ubuntu10.25","1.3.1-1ubuntu10.26","1.3.1-1ubuntu10.27","1.3.1-1ubuntu10.29","1.3.1-1ubuntu10.30","1.3.1-1ubuntu10.31"],"ecosystem_specific":{"binaries":[{"binary_name":"libvirt-bin","binary_version":"1.3.1-1ubuntu10.31"},{"binary_name":"libvirt-dev","binary_version":"1.3.1-1ubuntu10.31"},{"binary_name":"libvirt0","binary_version":"1.3.1-1ubuntu10.31"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3975.json"}},{"package":{"name":"libvirt","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/libvirt@4.0.0-1ubuntu8.21?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.0.0-1ubuntu8.21"}]}],"versions":["3.6.0-1ubuntu5","3.6.0-1ubuntu6","4.0.0-1ubuntu1","4.0.0-1ubuntu2","4.0.0-1ubuntu3","4.0.0-1ubuntu4","4.0.0-1ubuntu5","4.0.0-1ubuntu6","4.0.0-1ubuntu7","4.0.0-1ubuntu8","4.0.0-1ubuntu8.1","4.0.0-1ubuntu8.2","4.0.0-1ubuntu8.3","4.0.0-1ubuntu8.4","4.0.0-1ubuntu8.5","4.0.0-1ubuntu8.6","4.0.0-1ubuntu8.7","4.0.0-1ubuntu8.8","4.0.0-1ubuntu8.9","4.0.0-1ubuntu8.10","4.0.0-1ubuntu8.11","4.0.0-1ubuntu8.12","4.0.0-1ubuntu8.13","4.0.0-1ubuntu8.14","4.0.0-1ubuntu8.15","4.0.0-1ubuntu8.16","4.0.0-1ubuntu8.17","4.0.0-1ubuntu8.19","4.0.0-1ubuntu8.20"],"ecosystem_specific":{"binaries":[{"binary_name":"libnss-libvirt","binary_version":"4.0.0-1ubuntu8.21"},{"binary_name":"libvirt-bin","binary_version":"4.0.0-1ubuntu8.21"},{"binary_name":"libvirt-clients","binary_version":"4.0.0-1ubuntu8.21"},{"binary_name":"libvirt-daemon","binary_version":"4.0.0-1ubuntu8.21"},{"binary_name":"libvirt-daemon-driver-storage-gluster","binary_version":"4.0.0-1ubuntu8.21"},{"binary_name":"libvirt-daemon-driver-storage-rbd","binary_version":"4.0.0-1ubuntu8.21"},{"binary_name":"libvirt-daemon-driver-storage-sheepdog","binary_version":"4.0.0-1ubuntu8.21"},{"binary_name":"libvirt-daemon-driver-storage-zfs","binary_version":"4.0.0-1ubuntu8.21"},{"b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