{"id":"CVE-2021-47255","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nkvm: LAPIC: Restore guard to prevent illegal APIC register access\n\nPer the SDM, \"any access that touches bytes 4 through 15 of an APIC\nregister may cause undefined behavior and must not be executed.\"\nWorse, such an access in kvm_lapic_reg_read can result in a leak of\nkernel stack contents. Prior to commit 01402cf81051 (\"kvm: LAPIC:\nwrite down valid APIC registers\"), such an access was explicitly\ndisallowed. Restore the guard that was removed in that commit.","modified":"2026-03-23T05:12:37.457796Z","published":"2024-05-21T15:15:14.303Z","related":["SUSE-SU-2024:2010-1","SUSE-SU-2024:2183-1","SUSE-SU-2024:2185-1","SUSE-SU-2025:01995-1"],"references":[{"type":"FIX","url":"https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6"},{"type":"FIX","url":"https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210"},{"type":"FIX","url":"https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84"},{"type":"FIX","url":"https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5"}],"affected":[{"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47255.json","unresolved_ranges":[{"events":[{"introduced":"5.3"},{"fixed":"5.4.128"}]},{"events":[{"introduced":"5.5"},{"fixed":"5.10.46"}]},{"events":[{"introduced":"5.11"},{"fixed":"5.12.13"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc1"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc2"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc3"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc4"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc5"}]},{"events":[{"introduced":"0"},{"last_affected":"5.13-rc6"}]}]}}],"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:N/A:H"}]}