{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2021-47092",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-47092",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-03-04T18:10:40.037Z",
    "updatedAt": "2026-05-11T13:47:53.402Z",
    "importedAt": "2026-10-24T01:56:36.661Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "KVM: VMX: Always clear vmx->fail on emulation_required",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: VMX: Always clear vmx->fail on emulation_required\n\nRevert a relatively recent change that set vmx->fail if the vCPU is in L2\nand emulation_required is true, as that behavior is completely bogus.\nSetting vmx->fail and synthesizing a VM-Exit is contradictory and wrong:\n\n  (a) it's impossible to have both a VM-Fail and VM-Exit\n  (b) vmcs.EXIT_REASON is not modified on VM-Fail\n  (c) emulation_required refers to guest state and guest state checks are\n      always VM-Exits, not VM-Fails.\n\nFor KVM specifically, emulation_required is handled before nested exits\nin __vmx_handle_exit(), thus setting vmx->fail has no immediate effect,\ni.e. KVM calls into handle_invalid_guest_state() and vmx->fail is ignored.\nSetting vmx->fail can ultimately result in a WARN in nested_vmx_vmexit()\nfiring when tearing down the VM as KVM never expects vmx->fail to be set\nwhen L2 is active, KVM always reflects those errors into L1.\n\n  ------------[ cut here ]------------\n  WARNING: CPU: 0 PID: 21158 at arch/x86/kvm/vmx/nested.c:4548\n                                nested_vmx_vmexit+0x16bd/0x17e0\n                                arch/x86/kvm/vmx/nested.c:4547\n  Modules linked in:\n  CPU: 0 PID: 21158 Comm: syz-executor.1 Not tainted 5.16.0-rc3-syzkaller #0\n  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\n  RIP: 0010:nested_vmx_vmexit+0x16bd/0x17e0 arch/x86/kvm/vmx/nested.c:4547\n  Code: <0f> 0b e9 2e f8 ff ff e8 57 b3 5d 00 0f 0b e9 00 f1 ff ff 89 e9 80\n  Call Trace:\n   vmx_leave_nested arch/x86/kvm/vmx/nested.c:6220 [inline]\n   nested_vmx_free_vcpu+0x83/0xc0 arch/x86/kvm/vmx/nested.c:330\n   vmx_free_vcpu+0x11f/0x2a0 arch/x86/kvm/vmx/vmx.c:6799\n   kvm_arch_vcpu_destroy+0x6b/0x240 arch/x86/kvm/x86.c:10989\n   kvm_vcpu_destroy+0x29/0x90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:441\n   kvm_free_vcpus arch/x86/kvm/x86.c:11426 [inline]\n   kvm_arch_destroy_vm+0x3ef/0x6b0 arch/x86/kvm/x86.c:11545\n   kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:1189 [inline]\n   kvm_put_kvm+0x751/0xe40 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1220\n   kvm_vcpu_release+0x53/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3489\n   __fput+0x3fc/0x870 fs/file_table.c:280\n   task_work_run+0x146/0x1c0 kernel/task_work.c:164\n   exit_task_work include/linux/task_work.h:32 [inline]\n   do_exit+0x705/0x24f0 kernel/exit.c:832\n   do_group_exit+0x168/0x2d0 kernel/exit.c:929\n   get_signal+0x1740/0x2120 kernel/signal.c:2852\n   arch_do_signal_or_restart+0x9c/0x730 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+0x191/0x220 kernel/entry/common.c:207\n   __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]\n   syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300\n   do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86\n   entry_SYSCALL_64_after_hwframe+0x44/0xae",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "c8607e4a086fae05efe5bffb47c5199c65e7216e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "e4e4e7cb229821cd215031abc47efdab5486a67c"
            },
            {
              "version": "c8607e4a086fae05efe5bffb47c5199c65e7216e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a80dfc025924024d2c61a4c1b8ef62b2fce76a04"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.15",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.15"
            },
            {
              "version": "5.15.12",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "5.16",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}