{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2023-53756",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-12-08T01:18:04.280Z",
        "datePublished": "2025-12-08T01:19:17.081Z",
        "dateUpdated": "2026-05-11T19:51:04.572Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-05-11T19:51:04.572Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: VMX: Fix crash due to uninitialized current_vmcs\n\nKVM enables 'Enlightened VMCS' and 'Enlightened MSR Bitmap' when running as\na nested hypervisor on top of Hyper-V. When MSR bitmap is updated,\nevmcs_touch_msr_bitmap function uses current_vmcs per-cpu variable to mark\nthat the msr bitmap was changed.\n\nvmx_vcpu_create() modifies the msr bitmap via vmx_disable_intercept_for_msr\n-> vmx_msr_bitmap_l01_changed which in the end calls this function. The\nfunction checks for current_vmcs if it is null but the check is\ninsufficient because current_vmcs is not initialized. Because of this, the\ncode might incorrectly write to the structure pointed by current_vmcs value\nleft by another task. Preemption is not disabled, the current task can be\npreempted and moved to another CPU while current_vmcs is accessed multiple\ntimes from evmcs_touch_msr_bitmap() which leads to crash.\n\nThe manipulation of MSR bitmaps by callers happens only for vmcs01 so the\nsolution is to use vmx->vmcs01.vmcs instead of current_vmcs.\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000338\n  PGD 4e1775067 P4D 0\n  Oops: 0002 [#1] PREEMPT SMP NOPTI\n  ...\n  RIP: 0010:vmx_msr_bitmap_l01_changed+0x39/0x50 [kvm_intel]\n  ...\n  Call Trace:\n   vmx_disable_intercept_for_msr+0x36/0x260 [kvm_intel]\n   vmx_vcpu_create+0xe6/0x540 [kvm_intel]\n   kvm_arch_vcpu_create+0x1d1/0x2e0 [kvm]\n   kvm_vm_ioctl_create_vcpu+0x178/0x430 [kvm]\n   kvm_vm_ioctl+0x53f/0x790 [kvm]\n   __x64_sys_ioctl+0x8a/0xc0\n   do_syscall_64+0x5c/0x90\n   entry_SYSCALL_64_after_hwframe+0x63/0xcd"
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "arch/x86/kvm/vmx/hyperv.h",
                        "arch/x86/kvm/vmx/vmx.c"
                    ],
                    "versions": [
                        {
                            "version": "ceef7d10dfb6284d512c499292e6daa35ea83f90",
                            "lessThan": "6baebcecf09acd19e2bab1c2911dcdba5d48a1dc",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "ceef7d10dfb6284d512c499292e6daa35ea83f90",
                            "lessThan": "6e7bc50f97c9855da83f1478f722590defd45ff2",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "ceef7d10dfb6284d512c499292e6daa35ea83f90",
                            "lessThan": "b2de2b4d4e007f9add46ea8dc06f781835e3ea9f",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "ceef7d10dfb6284d512c499292e6daa35ea83f90",
                            "lessThan": "3ba95cc671c025d0d2a1c7d5e2930f0ff0980cf4",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "ceef7d10dfb6284d512c499292e6daa35ea83f90",
                            "lessThan": "93827a0a36396f2fd6368a54a020f420c8916e9b",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "arch/x86/kvm/vmx/hyperv.h",
                        "arch/x86/kvm/vmx/vmx.c"
                    ],
                    "versions": [
                        {
                            "version": "4.18",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "4.18",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.10.175",
                            "lessThanOrEqual": "5.10.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.15.103",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.16",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.2.3",
                            "lessThanOrEqual": "6.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.3",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.18",
                                    "versionEndExcluding": "5.10.175"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.18",
                                    "versionEndExcluding": "5.15.103"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.18",
                                    "versionEndExcluding": "6.1.16"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.18",
                                    "versionEndExcluding": "6.2.3"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.18",
                                    "versionEndExcluding": "6.3"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/6baebcecf09acd19e2bab1c2911dcdba5d48a1dc"
                },
                {
                    "url": "https://git.kernel.org/stable/c/6e7bc50f97c9855da83f1478f722590defd45ff2"
                },
                {
                    "url": "https://git.kernel.org/stable/c/b2de2b4d4e007f9add46ea8dc06f781835e3ea9f"
                },
                {
                    "url": "https://git.kernel.org/stable/c/3ba95cc671c025d0d2a1c7d5e2930f0ff0980cf4"
                },
                {
                    "url": "https://git.kernel.org/stable/c/93827a0a36396f2fd6368a54a020f420c8916e9b"
                }
            ],
            "title": "KVM: VMX: Fix crash due to uninitialized current_vmcs",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}