What is CVE-2021-47450?

CVE-2021-47450 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, affecting Linux kernel versions from 5.13 onward and patched in 5.14.15 and 5.15. CVE-2021-47450 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47450?

CVE-2021-47450 has a CVSS score of 5.5 out of 10, rated Medium severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2021-47450?

Yes, CVE-2021-47450 has been patched. Fixed versions include 5.14.15 and 5.15. If you are running Linux kernel 5.13 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2021-47450 actively exploited?

CVE-2021-47450 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2021-47450

Medium

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Fix host stage-2 PGD refcount The KVM page-table library refcounts the pages of concatenated stage-2 PGDs individually. However, when running KVM in protected mode, the host's stage-2 PGD is currently managed by EL2 as a single high-order compound page, which can cause the refcount of the tail pages to reach 0 when they shouldn't, hence corrupting the page-table. Fix this by introducing a new hyp_split_page() helper in the EL2 page allocator (matching the kernel's split_page() function), and make use of it from host_s2_zalloc_pages_exact().

Package Linux Kernel

Published 2024-05-22

Last modified 2025-09-24

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

5.5

out of 10

Medium

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected versions

Linux kernel versions 5.13 and later are affected. Fixed in 5.14.15, 5.15 and their respective stable series.

Affected from

≥ 5.13

Fixed in

✓ 5.14.15 5.14.x ✓ 5.15

References

2 total

Kernel Git
https://git.kernel.org/stable/c/1d58a17ef54599506d44c45ac95be27273a4d2b1

Patch
Kernel Git
https://git.kernel.org/stable/c/b372264c66ef78f2cab44e877fbd765ad6d24c39

Patch

Details

CVE ID CVE-2021-47450

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2024-05-22

Modified 2025-09-24

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2021-47450?

CVE-2021-47450 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 5.13 onward and has been patched in 5.14.15 and 5.15. CVE-2021-47450 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47450?

CVE-2021-47450 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2021-47450?

Yes. CVE-2021-47450 has been patched. Fixed versions include 5.14.15 and 5.15. If you are running Linux kernel 5.13 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2021-47450 actively exploited?

No. CVE-2021-47450 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.