{"id":"CVE-2026-89932","state":"PUBLISHED","title":"KVM: nVMX: Always flush vpid02 on first use","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nVMX: Always flush vpid02 on first use\n\nMake sure vpid02 is always flushed on first use by setting last_vpid=0\nwhen allocating vpid02.  nested_vmx_transition_tlb_flush() will always\ndetect a VPID change on first VM-Enter after VMXON, because VPID=0 in\nvmcs12 is not allowed if L1 enables VPID.\n\nThis avoids using stale TLB entries from a previous lifetime of the\nVPID, that might have been associated with a different vCPU (or a\ncompletely different VM).\n\nNote that last_vpid is already being initialized as 0 when the vCPU is\ncreated, but it is not reset when vpid02 is freed on VMXOFF. Hence, the\nproblem can only occur if L1 does VMXOFF -> VMXON, runs an L2, and KVM\nhappens to reuse a VPID that has TLB entries on the physical CPU.","publishedAt":"2026-09-16T10:32:22.886Z","updatedAt":"2026-10-19T08:55:06.898Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"26de0d2d9a8d14c03e5ebb25fd68b5bfcd5ac366","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"8bc609999ec223089fec8d74c7de27d689606b36","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"62604376c313178811375f40a282fc2a46cd2311","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"8b98d662ab24f34710a56e03bc9169e4a5508606","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"22dfcc22c95e91295119a1c3b469816ce44c4804","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"121991d150735f3c0f7401678ce4d35c5b4ac898","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"f0772389413dce9657c7d6950abf3edbbd511356","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kvm/vmx/nested.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.4","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","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/x86/kvm/vmx/nested.c"]}],"references":["https://git.kernel.org/stable/c/26de0d2d9a8d14c03e5ebb25fd68b5bfcd5ac366","https://git.kernel.org/stable/c/8bc609999ec223089fec8d74c7de27d689606b36","https://git.kernel.org/stable/c/62604376c313178811375f40a282fc2a46cd2311","https://git.kernel.org/stable/c/8b98d662ab24f34710a56e03bc9169e4a5508606","https://git.kernel.org/stable/c/22dfcc22c95e91295119a1c3b469816ce44c4804","https://git.kernel.org/stable/c/121991d150735f3c0f7401678ce4d35c5b4ac898","https://git.kernel.org/stable/c/f0772389413dce9657c7d6950abf3edbbd511356"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:26.108Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/89xxx/CVE-2026-89932.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89932","state":"PUBLISHED","datePublished":"2026-09-16T10:32:22.886Z","dateUpdated":"2026-10-19T08:55:06.898Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.776Z"},"containers":{"cna":{"title":"KVM: nVMX: Always flush vpid02 on first use","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nVMX: Always flush vpid02 on first use\n\nMake sure vpid02 is always flushed on first use by setting last_vpid=0\nwhen allocating vpid02.  nested_vmx_transition_tlb_flush() will always\ndetect a VPID change on first VM-Enter after VMXON, because VPID=0 in\nvmcs12 is not allowed if L1 enables VPID.\n\nThis avoids using stale TLB entries from a previous lifetime of the\nVPID, that might have been associated with a different vCPU (or a\ncompletely different VM).\n\nNote that last_vpid is already being initialized as 0 when the vCPU is\ncreated, but it is not reset when vpid02 is freed on VMXOFF. Hence, the\nproblem can only occur if L1 does VMXOFF -> VMXON, runs an L2, and KVM\nhappens to reuse a VPID that has TLB entries on the physical CPU."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"26de0d2d9a8d14c03e5ebb25fd68b5bfcd5ac366","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"8bc609999ec223089fec8d74c7de27d689606b36","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"62604376c313178811375f40a282fc2a46cd2311","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"8b98d662ab24f34710a56e03bc9169e4a5508606","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"22dfcc22c95e91295119a1c3b469816ce44c4804","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"121991d150735f3c0f7401678ce4d35c5b4ac898","versionType":"git"},{"version":"5c614b3583e7b6dab0c86356fa36c2bcbb8322a0","status":"affected","lessThan":"f0772389413dce9657c7d6950abf3edbbd511356","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kvm/vmx/nested.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.4","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","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/x86/kvm/vmx/nested.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/26de0d2d9a8d14c03e5ebb25fd68b5bfcd5ac366"},{"url":"https://git.kernel.org/stable/c/8bc609999ec223089fec8d74c7de27d689606b36"},{"url":"https://git.kernel.org/stable/c/62604376c313178811375f40a282fc2a46cd2311"},{"url":"https://git.kernel.org/stable/c/8b98d662ab24f34710a56e03bc9169e4a5508606"},{"url":"https://git.kernel.org/stable/c/22dfcc22c95e91295119a1c3b469816ce44c4804"},{"url":"https://git.kernel.org/stable/c/121991d150735f3c0f7401678ce4d35c5b4ac898"},{"url":"https://git.kernel.org/stable/c/f0772389413dce9657c7d6950abf3edbbd511356"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Reached when an L1 nested-VMX guest executes VMXOFF then VMXON and VMLAUNCH/VMRESUME on the host KVM_RUN path (handle_vmxon/enter_vmx_operation into nested_vmx_transition_tlb_flush); no network, adjacent-radio, or physical path hits nVMX VPID allocation.\nAC:L - The L1 attacker fully controls VMXOFF, VMXON, vmcs12 VPID, and vCPU pinning; allocate_vpid() is a deterministic global bitmap, nested VMX and VPID are default, and skipping last_vpid=0 makes the omitted INVVPID on first VM-Enter after VMXON reliably hit.\nPR:L - Needs /dev/kvm and nested VMX, typically a kvm-group user or cloud tenant running QEMU, not init-namespace root; handle_vmxon() only checks guest CPL=0 and CR4.VMXE, and KVM create/run ioctls have no CAP_SYS_ADMIN gate.\nUI:N - Once the attacker has a nested-capable VM, they trigger the flaw with their own VMXOFF/VMXON and VMLAUNCH; no separate victim action such as attaching a device or mounting a filesystem is required.\nS:C - Skipping the vpid02 INVVPID lets L2 use stale hardware TLB entries from a previous lifetime of that VPID, including another vCPU or a different VM, crossing KVM guest isolation so impact is outside L1's security authority.\nC:H - Reused vpid02 linear or combined TLB entries can translate L2 loads onto another VM's or recycled host physical pages, giving a read primitive over co-resident guest memory rather than a bounded pointer leak.\nI:H - The same stale translations apply to stores, so L2 can write through another VM's cached GPA/HPA mappings, corrupting co-resident guest memory and enabling control-flow hijack in the victim VM or further host compromise if pages were reused.\nA:H - Stale VPID hits produce wrong translations that surface as KVM internal/emulation failures and can oops or panic the host when walks land on recycled or unmapped host pages, denying service to the hypervisor and co-located VMs."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:55:06.898Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}