CVE-2021-47450

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().

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/1d58a17ef54599506d44c45ac95be27273a4d2b1	Patch
https://git.kernel.org/stable/c/b372264c66ef78f2cab44e877fbd765ad6d24c39	Patch
https://git.kernel.org/stable/c/1d58a17ef54599506d44c45ac95be27273a4d2b1	Patch
https://git.kernel.org/stable/c/b372264c66ef78f2cab44e877fbd765ad6d24c39	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:5.15:rc1::::::
	cpe:2.3:o:linux:linux_kernel:5.15:rc2::::::
	cpe:2.3:o:linux:linux_kernel:5.15:rc3::::::
	cpe:2.3:o:linux:linux_kernel:5.15:rc4::::::
	cpe:2.3:o:linux:linux_kernel:5.15:rc5::::::
	cpe:2.3:o:linux:linux_kernel:5.15:rc6::::::

History

No history.

Information

Published : 2024-05-22 07:15

Updated : 2025-09-24 01:07

NVD link : CVE-2021-47450

Mitre link : CVE-2021-47450

CVE.ORG link : CVE-2021-47450

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-Other

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