{"id":"CVE-2026-98638","state":"PUBLISHED","title":"KVM: arm64: Validate the SVE vector length in pkvm_vcpu_init_sve()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Validate the SVE vector length in pkvm_vcpu_init_sve()\n\npkvm_vcpu_init_sve() clamps only the upper bound of the host-provided\nsve_max_vl, so an invalid vector length reaches sve_state_size_from_vl()\nand the WARN_ON() there, which is fatal at EL2. The existing\n!sve_state_size test rejects such a length, but only after the macro has\nrun.\n\nCheck sve_vl_valid() before deriving the state size. A valid length\ncannot yield a zero size, so the !sve_state_size test goes with it.","publishedAt":"2026-10-18T15:20:09.380Z","updatedAt":"2026-10-19T09:23:08.052Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5db1bef933427aa467ad89c7b695a84a6b4afe16","status":"affected","lessThan":"faf66e55e87498ab4bf88cdf9a629e61b3f2d3bc","versionType":"git"},{"version":"5db1bef933427aa467ad89c7b695a84a6b4afe16","status":"affected","lessThan":"bae3e4493046de4fefa15f809d9b8dc114e84a3d","versionType":"git"},{"version":"5db1bef933427aa467ad89c7b695a84a6b4afe16","status":"affected","lessThan":"2a2eb10795a1e495aebc7f829ccecb72c05b4fd9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/nvhe/pkvm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.18.55","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/nvhe/pkvm.c"]}],"references":["https://git.kernel.org/stable/c/faf66e55e87498ab4bf88cdf9a629e61b3f2d3bc","https://git.kernel.org/stable/c/bae3e4493046de4fefa15f809d9b8dc114e84a3d","https://git.kernel.org/stable/c/2a2eb10795a1e495aebc7f829ccecb72c05b4fd9"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98638.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98638","state":"PUBLISHED","datePublished":"2026-10-18T15:20:09.380Z","dateUpdated":"2026-10-19T09:23:08.052Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.361Z"},"containers":{"cna":{"title":"KVM: arm64: Validate the SVE vector length in pkvm_vcpu_init_sve()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Validate the SVE vector length in pkvm_vcpu_init_sve()\n\npkvm_vcpu_init_sve() clamps only the upper bound of the host-provided\nsve_max_vl, so an invalid vector length reaches sve_state_size_from_vl()\nand the WARN_ON() there, which is fatal at EL2. The existing\n!sve_state_size test rejects such a length, but only after the macro has\nrun.\n\nCheck sve_vl_valid() before deriving the state size. A valid length\ncannot yield a zero size, so the !sve_state_size test goes with it."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5db1bef933427aa467ad89c7b695a84a6b4afe16","status":"affected","lessThan":"faf66e55e87498ab4bf88cdf9a629e61b3f2d3bc","versionType":"git"},{"version":"5db1bef933427aa467ad89c7b695a84a6b4afe16","status":"affected","lessThan":"bae3e4493046de4fefa15f809d9b8dc114e84a3d","versionType":"git"},{"version":"5db1bef933427aa467ad89c7b695a84a6b4afe16","status":"affected","lessThan":"2a2eb10795a1e495aebc7f829ccecb72c05b4fd9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/nvhe/pkvm.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.16","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.16","versionType":"semver"},{"version":"6.18.55","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.9","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/hyp/nvhe/pkvm.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/faf66e55e87498ab4bf88cdf9a629e61b3f2d3bc"},{"url":"https://git.kernel.org/stable/c/bae3e4493046de4fefa15f809d9b8dc114e84a3d"},{"url":"https://git.kernel.org/stable/c/2a2eb10795a1e495aebc7f829ccecb72c05b4fd9"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:23:08.052Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"6.18.55"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"7.2.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.16","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}