{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-40102",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-04-16T07:20:57.164Z",
        "datePublished": "2025-10-30T09:48:07.790Z",
        "dateUpdated": "2026-05-11T21:42:33.325Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-05-11T21:42:33.325Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Prevent access to vCPU events before init\n\nAnother day, another syzkaller bug. KVM erroneously allows userspace to\npend vCPU events for a vCPU that hasn't been initialized yet, leading to\nKVM interpreting a bunch of uninitialized garbage for routing /\ninjecting the exception.\n\nIn one case the injection code and the hyp disagree on whether the vCPU\nhas a 32bit EL1 and put the vCPU into an illegal mode for AArch64,\ntripping the BUG() in exception_target_el() during the next injection:\n\n  kernel BUG at arch/arm64/kvm/inject_fault.c:40!\n  Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP\n  CPU: 3 UID: 0 PID: 318 Comm: repro Not tainted 6.17.0-rc4-00104-g10fd0285305d #6 PREEMPT\n  Hardware name: linux,dummy-virt (DT)\n  pstate: 21402009 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)\n  pc : exception_target_el+0x88/0x8c\n  lr : pend_serror_exception+0x18/0x13c\n  sp : ffff800082f03a10\n  x29: ffff800082f03a10 x28: ffff0000cb132280 x27: 0000000000000000\n  x26: 0000000000000000 x25: ffff0000c2a99c20 x24: 0000000000000000\n  x23: 0000000000008000 x22: 0000000000000002 x21: 0000000000000004\n  x20: 0000000000008000 x19: ffff0000c2a99c20 x18: 0000000000000000\n  x17: 0000000000000000 x16: 0000000000000000 x15: 00000000200000c0\n  x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000\n  x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000\n  x8 : ffff800082f03af8 x7 : 0000000000000000 x6 : 0000000000000000\n  x5 : ffff800080f621f0 x4 : 0000000000000000 x3 : 0000000000000000\n  x2 : 000000000040009b x1 : 0000000000000003 x0 : ffff0000c2a99c20\n  Call trace:\n   exception_target_el+0x88/0x8c (P)\n   kvm_inject_serror_esr+0x40/0x3b4\n   __kvm_arm_vcpu_set_events+0xf0/0x100\n   kvm_arch_vcpu_ioctl+0x180/0x9d4\n   kvm_vcpu_ioctl+0x60c/0x9f4\n   __arm64_sys_ioctl+0xac/0x104\n   invoke_syscall+0x48/0x110\n   el0_svc_common.constprop.0+0x40/0xe0\n   do_el0_svc+0x1c/0x28\n   el0_svc+0x34/0xf0\n   el0t_64_sync_handler+0xa0/0xe4\n   el0t_64_sync+0x198/0x19c\n  Code: f946bc01 b4fffe61 9101e020 17fffff2 (d4210000)\n\nReject the ioctls outright as no sane VMM would call these before\nKVM_ARM_VCPU_INIT anyway. Even if it did the exception would've been\nthrown away by the eventual reset of the vCPU's state."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "arch/arm64/kvm/arm.c"
                    ],
                    "versions": [
                        {
                            "version": "b7b27facc7b50a5fce0afaa3df56157136ce181a",
                            "lessThan": "64a04e6320fc5affbadc59dc7024d79f909bfe84",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b7b27facc7b50a5fce0afaa3df56157136ce181a",
                            "lessThan": "0aa1b76fe1429629215a7c79820e4b96233ac4a3",
                            "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/arm64/kvm/arm.c"
                    ],
                    "versions": [
                        {
                            "version": "4.19",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "4.19",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.17.5",
                            "lessThanOrEqual": "6.17.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18",
                            "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": "4.19",
                                    "versionEndExcluding": "6.17.5"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.19",
                                    "versionEndExcluding": "6.18"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/64a04e6320fc5affbadc59dc7024d79f909bfe84"
                },
                {
                    "url": "https://git.kernel.org/stable/c/0aa1b76fe1429629215a7c79820e4b96233ac4a3"
                }
            ],
            "title": "KVM: arm64: Prevent access to vCPU events before init",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}