{"id":"UBUNTU-CVE-2021-3748","details":"A use-after-free vulnerability was found in the virtio-net device of QEMU. It could occur when the descriptor's address belongs to the non direct access region, due to num_buffers being set after the virtqueue elem has been unmapped. A malicious guest could use this flaw to crash QEMU, resulting in a denial of service condition, or potentially execute code on the host with the privileges of the QEMU process.","modified":"2026-01-30T02:53:27.854616Z","published":"2021-08-31T00:00:00Z","related":["USN-5307-1"],"upstream":["CVE-2021-3748"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-3748"},{"type":"REPORT","url":"https://lists.nongnu.org/archive/html/qemu-devel/2021-09/msg00388.html"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5307-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-3748"}],"affected":[{"package":{"name":"qemu","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/qemu@1:2.11+dfsg-1ubuntu7.39?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:2.11+dfsg-1ubuntu7.39"}]}],"versions":["1:2.10+dfsg-0ubuntu3","1:2.10+dfsg-0ubuntu4","1:2.10+dfsg-0ubuntu5","1:2.11+dfsg-1ubuntu1","1:2.11+dfsg-1ubuntu2","1:2.11+dfsg-1ubuntu4","1:2.11+dfsg-1ubuntu5","1:2.11+dfsg-1ubuntu6","1:2.11+dfsg-1ubuntu7","1:2.11+dfsg-1ubuntu7.1","1:2.11+dfsg-1ubuntu7.2","1:2.11+dfsg-1ubuntu7.3","1:2.11+dfsg-1ubuntu7.4","1:2.11+dfsg-1ubuntu7.5","1:2.11+dfsg-1ubuntu7.6","1:2.11+dfsg-1ubuntu7.7","1:2.11+dfsg-1ubuntu7.8","1:2.11+dfsg-1ubuntu7.9","1:2.11+dfsg-1ubuntu7.10","1:2.11+dfsg-1ubuntu7.12","1:2.11+dfsg-1ubuntu7.13","1:2.11+dfsg-1ubuntu7.14","1:2.11+dfsg-1ubuntu7.15","1:2.11+dfsg-1ubuntu7.17","1:2.11+dfsg-1ubuntu7.18","1:2.11+dfsg-1ubuntu7.19","1:2.11+dfsg-1ubuntu7.20","1:2.11+dfsg-1ubuntu7.21","1:2.11+dfsg-1ubuntu7.22","1:2.11+dfsg-1ubuntu7.23","1:2.11+dfsg-1ubuntu7.25","1:2.11+dfsg-1ubuntu7.26","1:2.11+dfsg-1ubuntu7.27","1:2.11+dfsg-1ubuntu7.28","1:2.11+dfsg-1ubuntu7.29","1:2.11+dfsg-1ubuntu7.31","1:2.11+dfsg-1ubuntu7.32","1:2.11+dfsg-1ubuntu7.33","1:2.11+dfsg-1ubuntu7.34","1:2.11+dfsg-1ubuntu7.35","1:2.11+dfsg-1ubuntu7.36","1:2.11+dfsg-1ubuntu7.37","1:2.11+dfsg-1ubuntu7.38"],"ecosystem_specific":{"availability":"No 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