CVE-2022-48763

{"id": "CVE-2022-48763", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2024-06-20T12:15:14.363", "references": [{"url": "https://git.kernel.org/stable/c/080dbe7e9b86a0392d8dffc00d9971792afc121f", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b4c0d89c92e957ecccce12e66b63875d0cc7af7e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/e302786233e6bc512986d007c96458ccf5ca21c7", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/f7e570780efc5cec9b2ed1e0472a7da14e864fdb", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/080dbe7e9b86a0392d8dffc00d9971792afc121f", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/b4c0d89c92e957ecccce12e66b63875d0cc7af7e", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/e302786233e6bc512986d007c96458ccf5ca21c7", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/f7e570780efc5cec9b2ed1e0472a7da14e864fdb", "tags": ["Patch"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-401"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: Forcibly leave nested virt when SMM state is toggled\n\nForcibly leave nested virtualization operation if userspace toggles SMM\nstate via KVM_SET_VCPU_EVENTS or KVM_SYNC_X86_EVENTS. If userspace\nforces the vCPU out of SMM while it's post-VMXON and then injects an SMI,\nvmx_enter_smm() will overwrite vmx->nested.smm.vmxon and end up with both\nvmxon=false and smm.vmxon=false, but all other nVMX state allocated.\n\nDon't attempt to gracefully handle the transition as (a) most transitions\nare nonsencial, e.g. forcing SMM while L2 is running, (b) there isn't\nsufficient information to handle all transitions, e.g. SVM wants access\nto the SMRAM save state, and (c) KVM_SET_VCPU_EVENTS must precede\nKVM_SET_NESTED_STATE during state restore as the latter disallows putting\nthe vCPU into L2 if SMM is active, and disallows tagging the vCPU as\nbeing post-VMXON in SMM if SMM is not active.\n\nAbuse of KVM_SET_VCPU_EVENTS manifests as a WARN and memory leak in nVMX\ndue to failure to free vmcs01's shadow VMCS, but the bug goes far beyond\njust a memory leak, e.g. toggling SMM on while L2 is active puts the vCPU\nin an architecturally impossible state.\n\n WARNING: CPU: 0 PID: 3606 at free_loaded_vmcs arch/x86/kvm/vmx/vmx.c:2665 [inline]\n WARNING: CPU: 0 PID: 3606 at free_loaded_vmcs+0x158/0x1a0 arch/x86/kvm/vmx/vmx.c:2656\n Modules linked in:\n CPU: 1 PID: 3606 Comm: syz-executor725 Not tainted 5.17.0-rc1-syzkaller #0\n Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\n RIP: 0010:free_loaded_vmcs arch/x86/kvm/vmx/vmx.c:2665 [inline]\n RIP: 0010:free_loaded_vmcs+0x158/0x1a0 arch/x86/kvm/vmx/vmx.c:2656\n Code: <0f> 0b eb b3 e8 8f 4d 9f 00 e9 f7 fe ff ff 48 89 df e8 92 4d 9f 00\n Call Trace:\n <TASK>\n kvm_arch_vcpu_destroy+0x72/0x2f0 arch/x86/kvm/x86.c:11123\n kvm_vcpu_destroy arch/x86/kvm/../../../virt/kvm/kvm_main.c:441 [inline]\n kvm_destroy_vcpus+0x11f/0x290 arch/x86/kvm/../../../virt/kvm/kvm_main.c:460\n kvm_free_vcpus arch/x86/kvm/x86.c:11564 [inline]\n kvm_arch_destroy_vm+0x2e8/0x470 arch/x86/kvm/x86.c:11676\n kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:1217 [inline]\n kvm_put_kvm+0x4fa/0xb00 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1250\n kvm_vm_release+0x3f/0x50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1273\n __fput+0x286/0x9f0 fs/file_table.c:311\n task_work_run+0xdd/0x1a0 kernel/task_work.c:164\n exit_task_work include/linux/task_work.h:32 [inline]\n do_exit+0xb29/0x2a30 kernel/exit.c:806\n do_group_exit+0xd2/0x2f0 kernel/exit.c:935\n get_signal+0x4b0/0x28c0 kernel/signal.c:2862\n arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868\n handle_signal_work kernel/entry/common.c:148 [inline]\n exit_to_user_mode_loop kernel/entry/common.c:172 [inline]\n exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207\n __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]\n syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300\n do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n </TASK>"}, {"lang": "es", "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: KVM: x86: abandonar por la fuerza la virt anidada cuando se alterna el estado de SMM. Dejar por la fuerza la operaci\u00f3n de virtualizaci\u00f3n anidada si el espacio de usuario alterna el estado de SMM mediante KVM_SET_VCPU_EVENTS o KVM_SYNC_X86_EVENTS. Si el espacio de usuario fuerza a la vCPU a salir de SMM mientras es posterior a VMXON y luego inyecta un SMI, vmx_enter_smm() sobrescribir\u00e1 vmx-&gt;nested.smm.vmxon y terminar\u00e1 con vmxon=false y smm.vmxon=false, pero todos los dem\u00e1s Estado nVMX asignado. No intente manejar la transici\u00f3n con elegancia ya que (a) la mayor\u00eda de las transiciones no tienen sentido, por ejemplo, forzar SMM mientras se ejecuta L2, (b) no hay suficiente informaci\u00f3n para manejar todas las transiciones, por ejemplo, SVM quiere acceder al estado de guardado de SMRAM, y (c) KVM_SET_VCPU_EVENTS debe preceder a KVM_SET_NESTED_STATE durante la restauraci\u00f3n del estado, ya que este \u00faltimo no permite colocar la vCPU en L2 si SMM est\u00e1 activo y no permite etiquetar la vCPU como posterior a VMXON en SMM si SMM no est\u00e1 activo. El abuso de KVM_SET_VCPU_EVENTS se manifiesta como una ADVERTENCIA y una p\u00e9rdida de memoria en nVMX debido a una falla al liberar el VMCS oculto de vmcs01, pero el error va mucho m\u00e1s all\u00e1 de una simple p\u00e9rdida de memoria; por ejemplo, activar SMM mientras L2 est\u00e1 activo coloca la vCPU en un estado arquitect\u00f3nicamente imposible. ADVERTENCIA: CPU: 0 PID: 3606 en free_loaded_vmcs arch/x86/kvm/vmx/vmx.c:2665 [en l\u00ednea] ADVERTENCIA: CPU: 0 PID: 3606 en free_loaded_vmcs+0x158/0x1a0 arch/x86/kvm/vmx/vmx. c:2656 M\u00f3dulos vinculados en: CPU: 1 PID: 3606 Comm: syz-executor725 Not tainted 5.17.0-rc1-syzkaller #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:free_loaded_vmcs arch/x86/kvm/vmx/vmx.c:2665 [en l\u00ednea] RIP: 0010:free_loaded_vmcs+0x158/0x1a0 arch/x86/kvm/vmx/vmx.c:2656 C\u00f3digo: &lt;0f&gt; 0b eb b3 e8 8f 4d 9f 00 e9 f7 fe ff ff 48 89 df e8 92 4d 9f 00 Seguimiento de llamadas: kvm_arch_vcpu_destroy+0x72/0x2f0 arch/x86/kvm/x86.c:11123 kvm_vcpu_destroy arch/x86/kvm/../. ./../virt/kvm/kvm_main.c:441 [en l\u00ednea] kvm_destroy_vcpus+0x11f/0x290 arch/x86/kvm/../../../virt/kvm/kvm_main.c:460 kvm_free_vcpus arch/x86 /kvm/x86.c:11564 [en l\u00ednea] kvm_arch_destroy_vm+0x2e8/0x470 arch/x86/kvm/x86.c:11676 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c :1217 [en l\u00ednea] kvm_put_kvm+0x4fa/0xb00 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1250 kvm_vm_release+0x3f/0x50 arch/x86/kvm/../.. /../virt/kvm/kvm_main.c:1273 __fput+0x286/0x9f0 fs/file_table.c:311 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [en l\u00ednea] do_exit+0xb29/0x2a30 kernel/exit.c:806 do_group_exit+0xd2/0x2f0 kernel/exit.c:935 get_signal+0x4b0/0x28c0 kernel/signal.c:2862 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c :868 handle_signal_work kernel/entry/common.c:148 [en l\u00ednea] exit_to_user_mode_loop kernel/entry/common.c:172 [en l\u00ednea] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c :289 [en l\u00ednea] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 Entry_SYSCALL_64_after_hwframe+0x44/0xae "}], "lastModified": "2025-09-17T16:50:37.887", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E1703BE0-DACE-4EE3-BF9E-DADE1395AB63", "versionEndExcluding": "5.10.97"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DF69DD7C-FD57-4914-ABB0-FAEF87B0289D", "versionEndExcluding": "5.15.19", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "1AD9E77E-B27E-450C-8FD8-B64EC5FB002D", "versionEndExcluding": "5.16.5", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.17:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7BD5F8D9-54FA-4CB0-B4F0-CB0471FDDB2D"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}