{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2022-49884",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-05-01T14:05:17.241Z",
        "datePublished": "2025-05-01T14:10:30.589Z",
        "dateUpdated": "2026-08-05T08:56:33.067Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T08:56:33.067Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: Initialize gfn_to_pfn_cache locks in dedicated helper\n\nMove the gfn_to_pfn_cache lock initialization to another helper and\ncall the new helper during VM/vCPU creation.  There are race\nconditions possible due to kvm_gfn_to_pfn_cache_init()'s\nability to re-initialize the cache's locks.\n\nFor example: a race between ioctl(KVM_XEN_HVM_EVTCHN_SEND) and\nkvm_gfn_to_pfn_cache_init() leads to a corrupted shinfo gpc lock.\n\n                (thread 1)                |           (thread 2)\n                                          |\n kvm_xen_set_evtchn_fast                  |\n  read_lock_irqsave(&gpc->lock, ...)      |\n                                          | kvm_gfn_to_pfn_cache_init\n                                          |  rwlock_init(&gpc->lock)\n  read_unlock_irqrestore(&gpc->lock, ...) |\n\nRename \"cache_init\" and \"cache_destroy\" to activate+deactivate to\navoid implying that the cache really is destroyed/freed.\n\nNote, there more races in the newly named kvm_gpc_activate() that will\nbe addressed separately.\n\n[sean: call out that this is a bug fix]"
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 7.8,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:L - The bug is triggered via KVM ioctls (KVM_XEN_HVM_EVTCHN_SEND racing with KVM_XEN_HVM_SET_ATTR / gpc activate) on a VM fd from /dev/kvm, which requires local process access.\nAC:L - The attacker fully controls both sides of the race by running concurrent threads that issue EVTCHN_SEND while deactivating/reactivating the shared_info gfn_to_pfn_cache, so success does not depend on external conditions.\nPR:L - Exploitation needs only the ability to open /dev/kvm and create a VM (typically kvm-group membership); no CAP_SYS_ADMIN or real root is required along the ioctl path.\nUI:N - The attacker performs the ioctls directly against their own VM; no action by another user is required.\nS:U - The clear attack is host userspace with KVM access corrupting host kernel lock state, which is privilege escalation within the same security authority rather than a guest-to-host escape.\nC:H - Re-initializing an rwlock while it is held corrupts kernel synchronization state and can yield use-after-free / memory-corruption primitives (as related gpc races explicitly warn), enabling arbitrary confidentiality impact.\nI:H - Corrupted gpc locks and the resulting memory corruption can be leveraged for arbitrary kernel writes or control-flow hijacking, not merely a benign state inconsistency.\nA:H - Unlocking or using a re-initialized rwlock reliably causes kernel oops/BUG, hangs, or panic; the related inactive-cache race also demonstrates a direct NULL deref crash path."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "arch/x86/kvm/x86.c",
                        "arch/x86/kvm/xen.c",
                        "include/linux/kvm_host.h",
                        "virt/kvm/pfncache.c"
                    ],
                    "versions": [
                        {
                            "version": "982ed0de4753ed6e71dbd40f82a5a066baf133ed",
                            "lessThan": "61242001d6c9c253df7645dab090842d8da08764",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "982ed0de4753ed6e71dbd40f82a5a066baf133ed",
                            "lessThan": "52491a38b2c2411f3f0229dc6ad610349c704a41",
                            "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/x86.c",
                        "arch/x86/kvm/xen.c",
                        "include/linux/kvm_host.h",
                        "virt/kvm/pfncache.c"
                    ],
                    "versions": [
                        {
                            "version": "5.17",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.17",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.0.8",
                            "lessThanOrEqual": "6.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1",
                            "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": "5.17",
                                    "versionEndExcluding": "6.0.8"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.17",
                                    "versionEndExcluding": "6.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/61242001d6c9c253df7645dab090842d8da08764"
                },
                {
                    "url": "https://git.kernel.org/stable/c/52491a38b2c2411f3f0229dc6ad610349c704a41"
                }
            ],
            "title": "KVM: Initialize gfn_to_pfn_cache locks in dedicated helper",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}