CVE-2021-47255
Linux Kernel KVM LAPIC Access Control Vulnerability
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.
INFO
Published Date :
May 21, 2024, 3:15 p.m.
Last Modified :
April 30, 2025, 3:11 p.m.
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Remotely Exploitable :
No
Impact Score :
5.2
Exploitability Score :
1.8
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-47255.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-47255 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-47255 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Apr. 30, 2025
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H Added CWE NVD-CWE-Other Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.3 up to (excluding) 5.4.128 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.46 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.12.13 Added Reference Type CVE: https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5 Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6 Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210 Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84 Types: Patch -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5 Added Reference https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6 Added Reference https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210 Added Reference https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84 -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 28, 2024
Action Type Old Value New Value -
CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 21, 2024
Action Type Old Value New Value Added 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. Added Reference kernel.org https://git.kernel.org/stable/c/bf99ea52970caeb4583bdba1192c1f9b53b12c84 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/018685461a5b9a9a70e664ac77aef0d7415a3fd5 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/a2aff09807fbe4018c269d3773a629949058b210 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/218bf772bddd221489c38dde6ef8e917131161f6 [No types assigned]
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-47255 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-47255
weaknesses.