{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-46100",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-05-13T15:03:33.097Z",
        "datePublished": "2026-05-27T12:59:06.853Z",
        "dateUpdated": "2026-08-05T12:29:37.582Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:29:37.582Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs: afs: revert mmap_prepare() change\n\nPartially reverts commit 9d5403b1036c (\"fs: convert most other\ngeneric_file_*mmap() users to .mmap_prepare()\").\n\nThis is because the .mmap invocation establishes a refcount, but\n.mmap_prepare is called at a point where a merge or an allocation failure\nmight happen after the call, which would leak the refcount increment.\n\nFunctionality is being added to permit the use of .mmap_prepare in this\ncase, but in the interim, we need to fix this."
                }
            ],
            "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 refcount leak is set up by a local mmap() syscall on a file in a mounted AFS volume; although AFS is a network filesystem, the vulnerable code path is reached via a local syscall, not via remote packet processing.\nAC:L - A local user reliably forces the leaking path by mmap'ing adjacent compatible regions to cause a VMA merge after .mmap_prepare; the merge and the subsequent fileserver-driven open_mmaps traversal are repeatable and within the attacker's control.\nPR:L - Exploitation requires only an unprivileged local account able to open and mmap a readable file on the AFS mount; no elevated capabilities are needed.\nUI:N - The attacker performs the mmap themselves; no action by another user is required (the AFS mount is environmental setup, not interaction).\nS:U - The corrupted vnode and the impacted callback-break code are all within the kernel's own security authority; no boundary such as VM/IOMMU is crossed.\nC:H - The leaked refcount leaves a freed afs_vnode linked on open_mmaps, and a subsequent callback-break traversal yields a use-after-free whose freed slab object can be controlled to enable arbitrary kernel memory disclosure.\nI:H - The use-after-free on the afs_vnode (afs_inode_cachep) permits heap spraying of attacker-controlled contents, providing a write primitive and potential control-flow hijack.\nA:H - The dangling list entry causes kernel oops/panic on the next callback-break traversal, and sustained triggering also leaks vnodes, so availability is fully impacted."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/afs/file.c"
                    ],
                    "versions": [
                        {
                            "version": "9d5403b1036cdcd4be0f9f5568612c0e60e73d79",
                            "lessThan": "f51f85c044809fbd39ac8ae07ac99bc43ce32bd5",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "9d5403b1036cdcd4be0f9f5568612c0e60e73d79",
                            "lessThan": "48c7a0eaeea41da17d1d84d2d7a4c40be122b246",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "9d5403b1036cdcd4be0f9f5568612c0e60e73d79",
                            "lessThan": "fbfc6578eaca12daa0c09df1e9ba7f2c657b49da",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/afs/file.c"
                    ],
                    "versions": [
                        {
                            "version": "6.17",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.17",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.27",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0.4",
                            "lessThanOrEqual": "7.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1",
                            "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": "6.17",
                                    "versionEndExcluding": "6.18.27"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.17",
                                    "versionEndExcluding": "7.0.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.17",
                                    "versionEndExcluding": "7.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/f51f85c044809fbd39ac8ae07ac99bc43ce32bd5"
                },
                {
                    "url": "https://git.kernel.org/stable/c/48c7a0eaeea41da17d1d84d2d7a4c40be122b246"
                },
                {
                    "url": "https://git.kernel.org/stable/c/fbfc6578eaca12daa0c09df1e9ba7f2c657b49da"
                }
            ],
            "title": "fs: afs: revert mmap_prepare() change",
            "x_generator": {
                "engine": "bippy-1.2.0"
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}