{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-40087",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-04-16T07:20:57.162Z",
        "datePublished": "2025-10-30T09:47:56.675Z",
        "dateUpdated": "2026-08-05T12:07:40.146Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:07:40.146Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nNFSD: Define a proc_layoutcommit for the FlexFiles layout type\n\nAvoid a crash if a pNFS client should happen to send a LAYOUTCOMMIT\noperation on a FlexFiles layout."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                        "baseScore": 7.5,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:N - The vulnerable code is in the in-kernel NFS server (nfsd), reached by processing an NFSv4.1 LAYOUTCOMMIT operation received in a COMPOUND RPC from a remote client over TCP port 2049. No local access to the server is required.\nAC:L - Triggering is fully deterministic — the attacker simply issues LAYOUTGET followed by LAYOUTCOMMIT with lc_layout_type=LAYOUT_FLEX_FILES, and the unconditional call through the NULL ops->proc_layoutcommit fires every time; there is no race, timing window, or memory-layout dependency.\nPR:N - With the default AUTH_SYS flavor nfsd performs no credential verification — the client asserts its own uid, and NFSD_MAY_OWNER_OVERRIDE in the fh_verify() check is satisfied by simply claiming the file owner's uid. Any host permitted to reach the export can drive the whole sequence without possessing credentials on the server.\nUI:N - The attacker performs the mount, session setup, LAYOUTGET and LAYOUTCOMMIT entirely on their own; no action by any user or administrator on the NFS server is needed once the export is online.\nS:U - The crash occurs in the nfsd kernel thread within the same security authority as the affected kernel; no VM, IOMMU, or sandbox boundary is crossed.\nC:N - The defect is a call through a NULL function pointer, not a read of out-of-bounds or freed memory; no kernel data or pointer values are disclosed to the remote client.\nI:N - No memory is written and no control-flow hijack is achievable — the target address is 0, which cannot be mapped by a remote attacker, so no file or kernel data is modified.\nA:H - The NULL dereference produces a kernel oops that kills the nfsd service thread (full panic when panic_on_oops is set) and leaks the export/stateid references held by nfsd4_layoutcommit(), rendering the NFS server unavailable; it can be re-triggered at will."
                        }
                    ]
                }
            ],
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                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/nfsd/flexfilelayout.c"
                    ],
                    "versions": [
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                            "version": "9b9960a0ca4773e21c4b153ed355583946346b25",
                            "lessThan": "a75994dd879401c3e24ff51c2536559f1a53ea27",
                            "status": "affected",
                            "versionType": "git"
                        },
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                            "lessThan": "34d187e020cbda112a6c6f094f0ca5e6a8672b75",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "9b9960a0ca4773e21c4b153ed355583946346b25",
                            "lessThan": "ba88a53d7f5df4191583abf214214efe0cda91d2",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "9b9960a0ca4773e21c4b153ed355583946346b25",
                            "lessThan": "da9129ef77786839a3ccd1d7afeeab790bceaa1d",
                            "status": "affected",
                            "versionType": "git"
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                        {
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                            "lessThan": "f7353208c91ab004e0179c5fb6c365b0f132f9f0",
                            "status": "affected",
                            "versionType": "git"
                        },
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                            "version": "9b9960a0ca4773e21c4b153ed355583946346b25",
                            "lessThan": "a156af6a4dc38c2aa7c98e89520a70fb3b3e7df4",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "9b9960a0ca4773e21c4b153ed355583946346b25",
                            "lessThan": "785ec512afa80d0540f2ca797c0e56de747a6083",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "9b9960a0ca4773e21c4b153ed355583946346b25",
                            "lessThan": "4b47a8601b71ad98833b447d465592d847b4dc77",
                            "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/nfsd/flexfilelayout.c"
                    ],
                    "versions": [
                        {
                            "version": "4.8",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "4.8",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.4.301",
                            "lessThanOrEqual": "5.4.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.10.246",
                            "lessThanOrEqual": "5.10.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.15.196",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.158",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.114",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.55",
                            "lessThanOrEqual": "6.12.*",
                            "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": [
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                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "4.8",
                                    "versionEndExcluding": "5.4.301"
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                                    "vulnerable": true,
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/a75994dd879401c3e24ff51c2536559f1a53ea27"
                },
                {
                    "url": "https://git.kernel.org/stable/c/34d187e020cbda112a6c6f094f0ca5e6a8672b75"
                },
                {
                    "url": "https://git.kernel.org/stable/c/ba88a53d7f5df4191583abf214214efe0cda91d2"
                },
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                    "url": "https://git.kernel.org/stable/c/da9129ef77786839a3ccd1d7afeeab790bceaa1d"
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                    "url": "https://git.kernel.org/stable/c/f7353208c91ab004e0179c5fb6c365b0f132f9f0"
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                    "url": "https://git.kernel.org/stable/c/a156af6a4dc38c2aa7c98e89520a70fb3b3e7df4"
                },
                {
                    "url": "https://git.kernel.org/stable/c/785ec512afa80d0540f2ca797c0e56de747a6083"
                },
                {
                    "url": "https://git.kernel.org/stable/c/4b47a8601b71ad98833b447d465592d847b4dc77"
                }
            ],
            "title": "NFSD: Define a proc_layoutcommit for the FlexFiles layout type",
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}