GHSA-M98C-VHM9-HW9C
Vulnerability from github – Published: 2026-08-06 09:30 – Updated: 2026-08-06 09:30In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Grab vmcs12 on CR8 interception update iff vCPU is in guest mode
When updating CR8 intercepts, get vmcs12 if and only if the vCPU is in guest mode so that a future change can have update CR8 intercepts during vCPU creation, without running afoul of get_vmcs12()'s lockdep assertion.
------------[ cut here ]------------ debug_locks && !(lock_is_held(&(&vcpu->mutex)->dep_map) || !refcount_read(&vcpu->kvm->users_count)) WARNING: arch/x86/kvm/vmx/nested.h:61 at get_vmcs12 arch/x86/kvm/vmx/nested.h:60 [inline], CPU#0: syz.2.19/5879 WARNING: arch/x86/kvm/vmx/nested.h:61 at vmx_update_cr8_intercept+0x3de/0x4e0 arch/x86/kvm/vmx/vmx.c:6879, CPU#0: syz.2.19/5879 Modules linked in: CPU: 0 UID: 0 PID: 5879 Comm: syz.2.19 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 RIP: 0010:get_vmcs12 arch/x86/kvm/vmx/nested.h:60 [inline] RIP: 0010:vmx_update_cr8_intercept+0x3de/0x4e0 arch/x86/kvm/vmx/vmx.c:6879 Call Trace: apic_update_ppr arch/x86/kvm/lapic.c:984 [inline] kvm_lapic_reset+0x1c24/0x2980 arch/x86/kvm/lapic.c:3023 kvm_vcpu_reset+0x44c/0x1bf0 arch/x86/kvm/x86.c:12986 kvm_arch_vcpu_create+0x746/0x8b0 arch/x86/kvm/x86.c:12847 kvm_vm_ioctl_create_vcpu+0x428/0x930 virt/kvm/kvm_main.c:4201 kvm_vm_ioctl+0x893/0xd50 virt/kvm/kvm_main.c:5159 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f
No functional change intended.
{
"affected": [],
"aliases": [
"CVE-2026-64604"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-06T08:16:36Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: VMX: Grab vmcs12 on CR8 interception update iff vCPU is in guest mode\n\nWhen updating CR8 intercepts, get vmcs12 if and only if the vCPU is in\nguest mode so that a future change can have update CR8 intercepts during\nvCPU creation, without running afoul of get_vmcs12()\u0027s lockdep assertion.\n\n ------------[ cut here ]------------\n debug_locks \u0026\u0026 !(lock_is_held(\u0026(\u0026vcpu-\u003emutex)-\u003edep_map) || !refcount_read(\u0026vcpu-\u003ekvm-\u003eusers_count))\n WARNING: arch/x86/kvm/vmx/nested.h:61 at get_vmcs12 arch/x86/kvm/vmx/nested.h:60 [inline], CPU#0: syz.2.19/5879\n WARNING: arch/x86/kvm/vmx/nested.h:61 at vmx_update_cr8_intercept+0x3de/0x4e0 arch/x86/kvm/vmx/vmx.c:6879, CPU#0: syz.2.19/5879\n Modules linked in:\n CPU: 0 UID: 0 PID: 5879 Comm: syz.2.19 Not tainted syzkaller #0 PREEMPT(full)\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014\n RIP: 0010:get_vmcs12 arch/x86/kvm/vmx/nested.h:60 [inline]\n RIP: 0010:vmx_update_cr8_intercept+0x3de/0x4e0 arch/x86/kvm/vmx/vmx.c:6879\n Call Trace:\n \u003cTASK\u003e\n apic_update_ppr arch/x86/kvm/lapic.c:984 [inline]\n kvm_lapic_reset+0x1c24/0x2980 arch/x86/kvm/lapic.c:3023\n kvm_vcpu_reset+0x44c/0x1bf0 arch/x86/kvm/x86.c:12986\n kvm_arch_vcpu_create+0x746/0x8b0 arch/x86/kvm/x86.c:12847\n kvm_vm_ioctl_create_vcpu+0x428/0x930 virt/kvm/kvm_main.c:4201\n kvm_vm_ioctl+0x893/0xd50 virt/kvm/kvm_main.c:5159\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:597 [inline]\n __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n \u003c/TASK\u003e\n\nNo functional change intended.",
"id": "GHSA-m98c-vhm9-hw9c",
"modified": "2026-08-06T09:30:33Z",
"published": "2026-08-06T09:30:33Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64604"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/258ec63c0f281bf7b50f9de67c8e93b5b7be5ed4"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3dcfb04dd43b16fa1240fc6487fff578ad57264c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/570af5db081b87374594a00711ac5760d2ea6844"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7ef78d71ca713d8c00f7c34ddcf276c808143f77"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9a21f1defd96c6301c5fb462a78eb51b191bd2dd"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c7cd3605244c924249dea32632e1bc3e89bda543"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/db8407b9fd06d857a4a5e8bcff1d086d13007711"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ffaaff82336db84e9b58e7a3e81c2fd64e05ed7a"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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