{"id":"CVE-2026-98638","summary":"KVM: arm64: Validate the SVE vector length in pkvm_vcpu_init_sve()","details":"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.","modified":"2026-10-20T02:30:20.339558247Z","published":"2026-10-18T15:20:09.380Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98638.json","cna_assigner":"Linux"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2a2eb10795a1e495aebc7f829ccecb72c05b4fd9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bae3e4493046de4fefa15f809d9b8dc114e84a3d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/faf66e55e87498ab4bf88cdf9a629e61b3f2d3bc"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98638.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98638"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5db1bef933427aa467ad89c7b695a84a6b4afe16"},{"fixed":"faf66e55e87498ab4bf88cdf9a629e61b3f2d3bc"},{"fixed":"bae3e4493046de4fefa15f809d9b8dc114e84a3d"},{"fixed":"2a2eb10795a1e495aebc7f829ccecb72c05b4fd9"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98638.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.16.0"},{"fixed":"6.18.55"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.9"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98638.json"}}],"schema_version":"1.9.0"}