{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2021-47450","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-05-21T14:58:30.832Z","datePublished":"2024-05-22T06:19:41.443Z","dateUpdated":"2025-05-04T07:11:12.084Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2025-05-04T07:11:12.084Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Fix host stage-2 PGD refcount\n\nThe KVM page-table library refcounts the pages of concatenated stage-2\nPGDs individually. However, when running KVM in protected mode, the\nhost's stage-2 PGD is currently managed by EL2 as a single high-order\ncompound page, which can cause the refcount of the tail pages to reach 0\nwhen they shouldn't, hence corrupting the page-table.\n\nFix this by introducing a new hyp_split_page() helper in the EL2 page\nallocator (matching the kernel's split_page() function), and make use of\nit from host_s2_zalloc_pages_exact()."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/include/nvhe/gfp.h","arch/arm64/kvm/hyp/nvhe/mem_protect.c","arch/arm64/kvm/hyp/nvhe/page_alloc.c"],"versions":[{"version":"1025c8c0c6accfcbdc8f52ca1940160f65cd87d6","lessThan":"b372264c66ef78f2cab44e877fbd765ad6d24c39","status":"affected","versionType":"git"},{"version":"1025c8c0c6accfcbdc8f52ca1940160f65cd87d6","lessThan":"1d58a17ef54599506d44c45ac95be27273a4d2b1","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/include/nvhe/gfp.h","arch/arm64/kvm/hyp/nvhe/mem_protect.c","arch/arm64/kvm/hyp/nvhe/page_alloc.c"],"versions":[{"version":"5.13","status":"affected"},{"version":"0","lessThan":"5.13","status":"unaffected","versionType":"semver"},{"version":"5.14.15","lessThanOrEqual":"5.14.*","status":"unaffected","versionType":"semver"},{"version":"5.15","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"5.14.15"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"5.15"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/b372264c66ef78f2cab44e877fbd765ad6d24c39"},{"url":"https://git.kernel.org/stable/c/1d58a17ef54599506d44c45ac95be27273a4d2b1"}],"title":"KVM: arm64: Fix host stage-2 PGD refcount","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2021-47450","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-05-22T18:46:22.813390Z"}}}],"providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-06-04T17:14:28.577Z"}},{"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2024-08-04T05:39:59.495Z"},"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/b372264c66ef78f2cab44e877fbd765ad6d24c39","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/1d58a17ef54599506d44c45ac95be27273a4d2b1","tags":["x_transferred"]}]}]}}