CVE-2021-47450

MediumCVSS 5.5/10Last modified Aug 4, 2026

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().

Metrics

CVSS 3.1 5.5/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected software

No affected versions have been published.

Timeline

Published
May 22, 2024
Last modified
Aug 4, 2026
NVD status
Modified

Related CVEs from 2021

CVE-2021-474515.5In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_IDLETIMER: fix panic that occurs when timer_type has garbCVE-2021-474525.5In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: skip netdev events generated on netns removal syCVE-2021-474535.5In the Linux kernel, the following vulnerability has been resolved: ice: Avoid crash from unnecessary IDA free In the remove path, there iCVE-2021-474545.5In the Linux kernel, the following vulnerability has been resolved: powerpc/smp: do not decrement idle task preempt count in CPU offline WCVE-2021-474555.5In the Linux kernel, the following vulnerability has been resolved: ptp: Fix possible memory leak in ptp_clock_register() I got memory leaCVE-2021-474568.4In the Linux kernel, the following vulnerability has been resolved: can: peak_pci: peak_pci_remove(): fix UAF When remove the module peek_CVE-2021-474575.5In the Linux kernel, the following vulnerability has been resolved: can: isotp: isotp_sendmsg(): add result check for wait_event_interruptiCVE-2021-474587.8In the Linux kernel, the following vulnerability has been resolved: ocfs2: mount fails with buffer overflow in strlen Starting with kernelCVE-2021-474597.8In the Linux kernel, the following vulnerability has been resolved: can: j1939: j1939_netdev_start(): fix UAF for rx_kref of j1939_priv ItCVE-2021-474605.5In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix data corruption after conversion from inline format Commit CVE-2021-474614.7In the Linux kernel, the following vulnerability has been resolved: userfaultfd: fix a race between writeprotect and exit_mmap() A race isCVE-2021-474625.5In the Linux kernel, the following vulnerability has been resolved: mm/mempolicy: do not allow illegal MPOL_F_NUMA_BALANCING | MPOL_LOCAL i