vulnerability

Debian: CVE-2021-47255: linux -- security update

Severity
6
CVSS
(AV:L/AC:L/Au:S/C:C/I:N/A:C)
Published
May 21, 2024
Added
Jul 30, 2024
Modified
Mar 30, 2026

Description

In the Linux kernel, the following vulnerability has been resolved:

kvm: LAPIC: Restore guard to prevent illegal APIC register access

Per the SDM, "any access that touches bytes 4 through 15 of an APIC
register may cause undefined behavior and must not be executed."
Worse, such an access in kvm_lapic_reg_read can result in a leak of
kernel stack contents. Prior to commit 01402cf81051 ("kvm: LAPIC:
write down valid APIC registers"), such an access was explicitly
disallowed. Restore the guard that was removed in that commit.

Solution

debian-upgrade-linux
Title
Rapid7 Labs

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