{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-64300",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T15:36:31.778Z",
        "datePublished": "2026-07-25T08:49:36.372Z",
        "dateUpdated": "2026-08-17T04:52:58.194Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-17T04:52:58.194Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf/aux: Fix page UAF in map_range()\n\nmap_range() reads rb->aux_pages[], rb->aux_nr_pages and rb->aux_pgoff via\nperf_mmap_to_page() while holding only event->mmap_mutex. Those fields are\nserialized by rb->aux_mutex, and mmap_mutex is per event.\n\nThus, two events sharing one rb via PERF_EVENT_IOC_SET_OUTPUT can race\nrb_alloc_aux() with map_range(), leading to a page-UAF scenario as follows:\n\n  CPU 0                           CPU 1\n  =====                           =====\n  rb_alloc_aux()                  map_range()\n  [1]: allocate rb->aux_pages[0]\n  [2]: rb->aux_nr_pages++\n                                  [3]: perf_mmap_to_page()\n                                         returns rb->aux_pages[0]\n                                  [4]: map it as VM_PFNMAP\n  [5]: rb->aux_pgoff = 1\n\n  munmap the page\n  [6]: free rb->aux_pages[0]\n\nPages mapped as VM_PFNMAP have no refcount protection, so CPU 1 holds a\nmapping to a freed physical frame.\n\nFix this by taking rb->aux_mutex across the page walk in map_range()."
                }
            ],
            "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 - Exploitation uses local perf_event_open(), ioctl(), mmap(), and munmap() operations; no network or physical path reaches map_range().\nAC:L - The attacker controls both racing mappings and the freeing munmap(), can enlarge the AUX allocation window, and can retry without depending on victim-controlled conditions.\nPR:L - An ordinary unprivileged user can create task-scoped AUX events such as Intel PT with exclude_kernel enabled under the upstream default perf_event_paranoid setting.\nUI:N - The attacking process independently creates the events, races the mappings, frees the AUX buffer, and accesses the stale mapping without victim action.\nS:U - Exploitation compromises the host kernel from local userspace but does not inherently cross a separate virtualization or IOMMU security authority.\nC:H - The persistent VM_PFNMAP alias exposes whichever kernel allocation reuses the freed physical frame, enabling disclosure of sensitive kernel memory.\nI:H - The stale page is mapped at offset zero, where pfn_mkwrite permits writes, enabling corruption of a reused kernel page and potential control-flow hijacking.\nA:H - Writing through the stale PFN can corrupt arbitrary kernel-owned page contents and cause an oops, panic, or complete system compromise."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "kernel/events/core.c"
                    ],
                    "versions": [
                        {
                            "version": "b709eb872e19a19607bbb6d2975bc264d59735cf",
                            "lessThan": "c8b7e113f7b61eef2f017e6329c27c2331058c5a",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b709eb872e19a19607bbb6d2975bc264d59735cf",
                            "lessThan": "0cff05bd2186020f8706233e261016d149cc24db",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b709eb872e19a19607bbb6d2975bc264d59735cf",
                            "lessThan": "5948aaf64f81f217a25dcc2bf6c0779bca19566c",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "kernel/events/core.c"
                    ],
                    "versions": [
                        {
                            "version": "6.14",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.14",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.39",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.4",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2",
                            "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": "6.14",
                                    "versionEndExcluding": "6.18.39"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.14",
                                    "versionEndExcluding": "7.1.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.14",
                                    "versionEndExcluding": "7.2"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/c8b7e113f7b61eef2f017e6329c27c2331058c5a"
                },
                {
                    "url": "https://git.kernel.org/stable/c/0cff05bd2186020f8706233e261016d149cc24db"
                },
                {
                    "url": "https://git.kernel.org/stable/c/5948aaf64f81f217a25dcc2bf6c0779bca19566c"
                }
            ],
            "title": "perf/aux: Fix page UAF in map_range()",
            "x_generator": {
                "engine": "bippy-1.2.0"
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    }
}