{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-89612",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-09-11T19:38:34.734Z",
        "datePublished": "2026-09-11T19:45:13.415Z",
        "dateUpdated": "2026-10-19T08:49:44.526Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-10-19T08:49:44.526Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: reject invalid MFT LCNs from boot sector\n\nThe NTFS boot sector stores the MFT and MFTMirr locations as unsigned\n64-bit LCNs, but parse_ntfs_boot_sector() decoded them into an s64.\n\nA crafted high-bit value could therefore become negative and pass\nthe existing upper-bound check. The invalid value then propagated into\nthe MFT zone allocator and could result in an out-of-bounds access to\nlcn_empty_bits_per_page."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 9.8,
                        "baseSeverity": "CRITICAL"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:N - After a crafted NTFS volume is mounted, fs/ntfs registers ntfs_export_ops, so nfsd/ksmbd VFS writes and creates reach ntfs_cluster_alloc() and index the poisoned MFT-zone LCN into lcn_empty_bits_per_page without local shell access.\nAC:L - The attacker fully controls the unsigned 64-bit MFT/MFTMirr LCNs in the boot sector; a high-bit value becomes a negative s64, bypasses the signed upper-bound check, and later allocator walks use that value as bmp_pos with no race or rare config.\nPR:N - Triggering the allocator needs only write access to a mounted NTFS export (guest/anonymous SMB or a permissive NFS export) or an unprivileged write on an already-mounted volume, not init-namespace root or CAP_SYS_ADMIN at trigger time.\nUI:N - After the crafted volume is mounted and exported, ordinary remote or local write/create operations invoke ntfs_cluster_alloc() with the poisoned mft_zone_pos; no extra victim mount dialog or USB insertion is required during the attack.\nS:U - Out-of-bounds access to vol->lcn_empty_bits_per_page corrupts kernel heap within the host OS security domain and does not cross a VM, container, or IOMMU boundary to another authority.\nC:H - ntfs_cluster_alloc() reads lcn_empty_bits_per_page[index] where index is derived from the attacker-chosen negative LCN (truncating to a controllable pgoff_t on 32-bit), an unbounded kernel heap out-of-bounds read that can disclose adjacent objects.\nI:H - The same attacker-influenced index is passed to ntfs_set_lcn_empty_bits(), which increments or decrements lcn_empty_bits_per_page[index], a kernel heap out-of-bounds write exploitable for arbitrary write and control-flow hijacking.\nA:H - The out-of-bounds lcn_empty_bits_per_page index causes a kernel oops or KASAN slab-out-of-bounds fault in ntfs_cluster_alloc()/ntfs_set_lcn_empty_bits(), crashing or hanging the host even when not fully exploited."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/ntfs/super.c"
                    ],
                    "versions": [
                        {
                            "version": "11ccc9107dc460de28af90fac1f42404d9802735",
                            "lessThan": "8f8420b68a6f05ca2b03779d8208814ec539b9e5",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "11ccc9107dc460de28af90fac1f42404d9802735",
                            "lessThan": "cc9d09fef78410bcd37ac05168cbd5f6dd75d3d2",
                            "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/ntfs/super.c"
                    ],
                    "versions": [
                        {
                            "version": "7.1",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "7.1",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2.4",
                            "lessThanOrEqual": "7.2.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.3",
                            "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": "7.1",
                                    "versionEndExcluding": "7.2.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "7.1",
                                    "versionEndExcluding": "7.3"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/8f8420b68a6f05ca2b03779d8208814ec539b9e5"
                },
                {
                    "url": "https://git.kernel.org/stable/c/cc9d09fef78410bcd37ac05168cbd5f6dd75d3d2"
                }
            ],
            "title": "ntfs: reject invalid MFT LCNs from boot sector",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}