VULNERABILITY INTELLIGENCE
CVE-2021-47450
CVSS score8.8 HIGH
EPSS probability0.21%
CISA KEVNot currently listed
Published2024-05-22
Last modified2026-08-04
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Description
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().
Weakness classification
- nvd@nist.gov: NVD-CWE-Other