Vulnerability-Lookup

FKIE_CVE-2021-47450

Vulnerability from fkie_nvd - Published: 2024-05-22 07:15 - Updated: 2026-08-04 10:17

Severity

8.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Summary

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().

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/1d58a17ef54599506d44c45ac95be27273a4d2b1	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/b372264c66ef78f2cab44e877fbd765ad6d24c39	Patch
af854a3a-2127-422b-91ae-364da2661108	https://git.kernel.org/stable/c/1d58a17ef54599506d44c45ac95be27273a4d2b1	Patch
af854a3a-2127-422b-91ae-364da2661108	https://git.kernel.org/stable/c/b372264c66ef78f2cab44e877fbd765ad6d24c39	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	5.15
linux	linux_kernel	5.15
linux	linux_kernel	5.15
linux	linux_kernel	5.15
linux	linux_kernel	5.15
linux	linux_kernel	5.15

JSON

To clipboard

{
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          "programFiles": [
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    },
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    }
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}

CVE-2021-47450 (GCVE-0-2021-47450)

Vulnerability from cvelistv5 – Published: 2024-05-22 06:19 – Updated: 2026-08-05 08:47

Title

KVM: arm64: Fix host stage-2 PGD refcount

Summary

Severity

8.8 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-05-22 18:46 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6856 records in the last 180 days details

References

2 references

URL	Tags
https://git.kernel.org/stable/c/b372264c66ef78f2c…
https://git.kernel.org/stable/c/1d58a17ef54599506…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 1025c8c0c6accfcbdc8f52ca1940160f65cd87d6 , < b372264c66ef78f2cab44e877fbd765ad6d24c39 (git) Affected: 1025c8c0c6accfcbdc8f52ca1940160f65cd87d6 , < 1d58a17ef54599506d44c45ac95be27273a4d2b1 (git)
Linux	Linux	Affected: 5.13 Unaffected: 0 , < 5.13 (semver) Unaffected: 5.14.15 , ≤ 5.14.* (semver) Unaffected: 5.15 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

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