{"id":"CVE-2021-3444","details":"The bpf verifier in the Linux kernel did not properly handle mod32 destination register truncation when the source register was known to be 0. A local attacker with the ability to load bpf programs could use this gain out-of-bounds reads in kernel memory leading to information disclosure (kernel memory), and possibly out-of-bounds writes that could potentially lead to code execution. This issue was addressed in the upstream kernel in commit 9b00f1b78809 (\"bpf: Fix truncation handling for mod32 dst reg wrt zero\") and in Linux stable kernels 5.11.2, 5.10.19, and 5.4.101.","aliases":["A-183694099","PUB-A-183694099"],"modified":"2026-03-13T05:00:04.562238Z","published":"2021-03-23T18:15:13.627Z","related":["SUSE-SU-2021:1175-1","SUSE-SU-2021:1176-1","SUSE-SU-2021:1177-1","SUSE-SU-2021:1210-1","SUSE-SU-2021:1211-1","SUSE-SU-2021:1238-1","SUSE-SU-2021:1344-1","SUSE-SU-2021:1347-1","SUSE-SU-2021:1365-1","SUSE-SU-2021:1395-1","SUSE-SU-2021:1573-1","SUSE-SU-2021:1595-1","SUSE-SU-2021:1596-1","SUSE-SU-2021:1624-1","SUSE-SU-2021:1625-1","SUSE-SU-2021:1733-1","SUSE-SU-2021:1975-1","SUSE-SU-2021:1977-1","SUSE-SU-2021:2577-1","openSUSE-SU-2021:0532-1","openSUSE-SU-2021:0758-1","openSUSE-SU-2021:1975-1","openSUSE-SU-2021:1977-1"],"references":[{"type":"ADVISORY","url":"http://www.openwall.com/lists/oss-security/2021/03/23/2"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20210416-0006/"},{"type":"ADVISORY","url":"https://www.openwall.com/lists/oss-security/2021/03/23/2"},{"type":"ADVISORY","url":"http://packetstormsecurity.com/files/162117/Kernel-Live-Patch-Security-Notice-LSN-0075-1.html"},{"type":"ADVISORY","url":"http://packetstormsecurity.com/files/164950/Kernel-Live-Patch-Security-Notice-LSN-0082-1.html"},{"type":"FIX","url":"https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9b00f1b78809"}],"affected":[{"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-3444.json","unresolved_ranges":[{"events":[{"introduced":"0"},{"fixed":"5.4.101"}]},{"events":[{"introduced":"5.5.0"},{"fixed":"5.10.19"}]},{"events":[{"introduced":"5.11"},{"fixed":"5.11.2"}]},{"events":[{"introduced":"0"},{"last_affected":"9.0"}]},{"events":[{"introduced":"0"},{"last_affected":"14.04"}]},{"events":[{"introduced":"0"},{"last_affected":"16.04"}]},{"events":[{"introduced":"0"},{"last_affected":"18.04"}]},{"events":[{"introduced":"0"},{"last_affected":"20.04"}]}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}