CVE-2021-47450
published 2024-05-22CVE-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…
PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.21%
10.8th percentile
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().
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.15.3-1 (bookworm) | linux 5.15.3-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 1025c8c0c6accfcbdc8f52ca1940160f65cd87d6 < b372264c66ef78f2cab44e877fbd765ad6d24c39 | b372264c66ef78f2cab44e877fbd765ad6d24c39 |
| linux | linux | >= 1025c8c0c6accfcbdc8f52ca1940160f65cd87d6 < 1d58a17ef54599506d44c45ac95be27273a4d2b1 | 1d58a17ef54599506d44c45ac95be27273a4d2b1 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.15.3-1 | 5.15.3-1 |
| linux | linux_kernel | >= 0 < 5.15.3-1 | 5.15.3-1 |
| linux | linux_kernel | >= 0 < 5.15.3-1 | 5.15.3-1 |
| linux | linux_kernel | >= 5.13 < 5.14.15 | 5.14.15 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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Red Hat
kernel: KVM: arm64: Fix host stage-2 PGD refcount
vendor_redhat·2024-05-22·CVSS 5.5
CVE-2021-47450 [MEDIUM] CWE-99 kernel: KVM: arm64: Fix host stage-2 PGD refcount
kernel: KVM: arm64: Fix host stage-2 PGD refcount
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: kernel (Red Hat Enterprise Linux 6) - Not affected
Package: kernel (Red Hat Enterprise Linux 7) - Not affected
Debian
CVE-2021-47450: linux - In the Linux kernel, the following vulnerability has been resolved: KVM: arm64:...
vendor_debian·2021·CVSS 5.5
CVE-2021-47450 [MEDIUM] CVE-2021-47450: linux - In the Linux kernel, the following vulnerability has been resolved: KVM: arm64:...
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().
Scope: local
bookworm: resolved (fixed in 5.15.3-1)
bullseye: resolved
forky: resolved (fixed in 5.15.3-1)
sid: resolved (fixed in 5.15.3-1)
trixie: resolved (fixed in 5.15.
GHSA
GHSA-cmcr-4938-mjgj: In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Fix host stage-2 PGD refcount
The KVM page-table library refcounts t
ghsa_unreviewed·2024-05-22
CVE-2021-47450 [MEDIUM] GHSA-cmcr-4938-mjgj: In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Fix host stage-2 PGD refcount
The KVM page-table library refcounts t
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().
OSV
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
osv·2024-05-22·CVSS 5.5
CVE-2021-47450 [MEDIUM] 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
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().
No detection rules found.
No public exploits indexed.
2024-05-22
Published