{
  "schema_version": "1.6.1",
  "id": "RPI-CVE-2026-99176",
  "modified": "2026-10-29T05:30:01Z",
  "upstream": [
    "CVE-2026-99176"
  ],
  "published": "2026-10-28T11:36:32Z",
  "summary": "KVM: nVMX: Reset MMU back to the root MMU if loading L2 state fails for !VM-Entry",
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nVMX: Reset MMU back to the root MMU if loading L2 state fails for !VM-Entry\n\nReset the vCPU's MMU pointer back to the root MMU if loading L2 state fails\nin the \"not from VM-Entry\" case, i.e. when emulating RSM or handling\nKVM_SET_NESTED_STATE.  Failure to unwind the MMU pointer results in KVM\ntrying to run L1 with a nested MMU, and is especially problematic if the\nvCPU manages to free its nested state before the VM crashes.  Constructing\nthe root for a nested EPT MMU goes through vmcs12, which is dynamically\nallocated/freed when nVMX is enabled/disabled.  And so if the nested state\nis freed with the MMU still pointing at the nested MMU, KVM will hit a NULL\npointer deref when attempting to get L1=>L2 EPTP.\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000078\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 114a2d067 P4D 111743067 PUD 11141f067 PMD 0\n  Oops: Oops: 0000 [#1] SMP\n  CPU: 20 UID: 1000 PID: 1272 Comm: nested_tdp_faul Not tainted 7.3.0-rc4-8c89f11d1a99b-sink-vm #1914 PREEMPTLAZY\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:nested_ept_get_eptp+0xb/0x10 [kvm_intel]\n  Call Trace:\n   <TASK>\n   kvm_mmu_load+0xcd/0x870 [kvm]\n   kvm_arch_vcpu_ioctl_run+0x18f5/0x1f80 [kvm]\n   kvm_vcpu_ioctl+0x2c7/0x970 [kvm]\n   __x64_sys_ioctl+0x90/0xd0\n   do_syscall_64+0x9c/0x4d0\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n  RIP: 0033:0x47491b\n   </TASK>\n  Modules linked in: kvm_intel kvm irqbypass\n  CR2: 0000000000000078\n  ---[ end trace 0000000000000000 ]---\n  RIP: 0010:nested_ept_get_eptp+0xb/0x10 [kvm_intel]\n\n[sean: write changelog]",
  "affected": [
    {
      "package": {
        "ecosystem": "Raspberry Pi OS:12",
        "name": "linux"
      },
      "versions": [
        "1:6.1.47-1+rpt4"
      ],
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-2712",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v6",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l",
            "binary_version": "1:6.1.47-1+rpt4"
          },
          {
            "binary_name": "linux-image-6.1.0-rpi3-rpi-v8",
            "binary_version": "1:6.1.47-1+rpt4"
          }
        ]
      },
      "database_specific": {
        "per_version": {
          "1:6.1.47-1+rpt4": {
            "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e",
            "upstream_version": "6.1.47",
            "assessment": "commit ancestry (strak rule)",
            "upstream_fixed": null,
            "compiled_filter": false
          }
        }
      }
    }
  ],
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-99176"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/d00d5f534a8238674755e59826a6c7d3c8efb870"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c9716f956216eb74ab0aad7f633586edd49e0322"
    },
    {
      "type": "FIX",
      "url": "https://git.kernel.org/stable/c/c8f4cfe1cf93bce924e27f2abead7a4c4a487505"
    }
  ],
  "database_specific": {
    "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git",
    "upstream_modified": "2026-10-28T11:36:32Z"
  }
}