{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-31558",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-03-09T15:48:24.116Z",
        "datePublished": "2026-04-24T14:35:41.209Z",
        "dateUpdated": "2026-08-05T12:23:30.748Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:23:30.748Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nLoongArch: KVM: Make kvm_get_vcpu_by_cpuid() more robust\n\nkvm_get_vcpu_by_cpuid() takes a cpuid parameter whose type is int, so\ncpuid can be negative. Let kvm_get_vcpu_by_cpuid() return NULL for this\ncase so as to make it more robust.\n\nThis fix an out-of-bounds access to kvm_arch::phyid_map::phys_map[]."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
                        "baseScore": 8.8,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:L - Exploitation requires local ability to run/control a LoongArch KVM guest or access KVM ioctls through `/dev/kvm`; the vulnerable code is not reachable directly over a network.\nAC:L - The attacker can directly supply the negative CPUID condition through guest hypercall register state or KVM interrupt-controller state, and no race or external timing condition is required.\nPR:L - The attacker needs access to a KVM VM or `/dev/kvm`, but the path does not require real host root or an init-namespace capability once KVM access is available.\nUI:N - No victim user action is required after the attacker can run the guest/KVM operation; the trigger is a direct hypercall or ioctl-driven interrupt-controller operation.\nS:C - The vulnerable component is host KVM, and a malicious guest or KVM user can affect host kernel memory, crossing the VM isolation boundary.\nC:H - The bug is an out-of-bounds access to the host kernel `phys_map` array, and under the required higher-severity rule this is treated as potentially exposing host kernel memory during exploitation.\nI:H - If the out-of-bounds entry is interpreted as an enabled vCPU, later interrupt-injection paths dereference and modify state through a bogus `struct kvm_vcpu` pointer, making host kernel memory corruption defensible.\nA:H - The reported failure includes UBSAN out-of-bounds warnings in host KVM, and attacker-controlled negative indices can reasonably cause host kernel oops, panic, or repeated denial of service."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "arch/loongarch/kvm/vcpu.c"
                    ],
                    "versions": [
                        {
                            "version": "73516e9da512adc63ba3859fbd82a21f6257348f",
                            "lessThan": "596c3f8069c4792f22fce8c4452f44410032d910",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "73516e9da512adc63ba3859fbd82a21f6257348f",
                            "lessThan": "878cf6acb4fd8ab4126cf9d369a5bb0e23123418",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "73516e9da512adc63ba3859fbd82a21f6257348f",
                            "lessThan": "47857b05bd50db01e211a1b6f513d57901cd3e6b",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "73516e9da512adc63ba3859fbd82a21f6257348f",
                            "lessThan": "2db06c15d8c7a0ccb6108524e16cd9163753f354",
                            "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/loongarch/kvm/vcpu.c"
                    ],
                    "versions": [
                        {
                            "version": "6.10",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.10",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.80",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.21",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.19.11",
                            "lessThanOrEqual": "6.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0",
                            "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": "6.10",
                                    "versionEndExcluding": "6.12.80"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "6.18.21"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "6.19.11"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "7.0"
                                }
                            ]
                        }
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                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/596c3f8069c4792f22fce8c4452f44410032d910"
                },
                {
                    "url": "https://git.kernel.org/stable/c/878cf6acb4fd8ab4126cf9d369a5bb0e23123418"
                },
                {
                    "url": "https://git.kernel.org/stable/c/47857b05bd50db01e211a1b6f513d57901cd3e6b"
                },
                {
                    "url": "https://git.kernel.org/stable/c/2db06c15d8c7a0ccb6108524e16cd9163753f354"
                }
            ],
            "title": "LoongArch: KVM: Make kvm_get_vcpu_by_cpuid() more robust",
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}