{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-63910",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T07:54:57.020Z",
        "datePublished": "2026-07-19T14:55:15.770Z",
        "dateUpdated": "2026-08-05T12:37:04.026Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:37:04.026Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndma-buf: fix UAF in dma_buf_fd() tracepoint\n\nOnce FD_ADD() returns, the fd is live in the file descriptor table\nand a thread sharing that table can close() it before DMA_BUF_TRACE()\nruns. The close drops the last reference, __fput() frees the dma_buf,\nand the tracepoint then dereferences dmabuf to take dmabuf->name_lock\n-- slab-use-after-free.\n\nSplit FD_ADD() back into get_unused_fd_flags() + fd_install() and\nemit the tracepoint between them. While the fdtable slot is reserved\nwith a NULL file pointer, a racing close() returns -EBADF without\nentering __fput(), so the dma_buf stays alive across the trace. Same\napproach as commit 2d76319c4cbb (\"dma-buf: fix UAF in dma_buf_put()\ntracepoint\").\n\nThis undoes the FD_ADD() conversion done in commit 34dfce523c90\n(\"dma: convert dma_buf_fd() to FD_ADD()\"); FD_ADD() has no place to\nhook the tracepoint safely."
                }
            ],
            "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 UAF is reached only through local syscalls/ioctls (e.g. UDMABUF_CREATE, DMA_HEAP_IOCTL_ALLOC, DRM/videobuf2 buffer export) that call dma_buf_fd(); there is no network or physical-device entry point.\nAC:L - Exploitation requires a race between dma_buf_fd() and close() on a shared fd table, but the attacker controls both threads and can hammer the window concurrently; syzkaller demonstrated reliable triggering without conditions outside attacker control.\nPR:L - An unprivileged local user with access to dma-buf interfaces (udmabuf, dma_heap, DRM render node, or media devices) can reach dma_buf_fd(); syzbot confirmed unprivileged and user-namespace reachability without real root in the init namespace.\nUI:N - Exploitation is performed entirely by the attacker's own multi-threaded process issuing ioctls and close() calls; no action by a separate victim user is required.\nS:U - Impact is kernel memory corruption and privilege escalation within the same kernel security domain; this is standard local kernel compromise, not a VM escape or IOMMU/DMA boundary bypass.\nC:H - The bug is a slab use-after-free on struct dma_buf; the tracepoint dereferences freed memory (name_lock, exp_name, file fields), enabling controlled reuse of freed kmalloc-1k objects for arbitrary kernel memory disclosure.\nI:H - UAF on a kmalloc-1k kernel object with spinlock interaction provides heap corruption primitives that can be developed into arbitrary kernel writes and local privilege escalation.\nA:H - Winning the race causes a confirmed slab-use-after-free in dma_buf_fd() (KASAN/lockdep fault), which can panic or oops the kernel even when not fully exploited for code execution."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/dma-buf/dma-buf.c"
                    ],
                    "versions": [
                        {
                            "version": "281a226314238e8adb08d11b765347687ffb38b9",
                            "lessThan": "b569f86e2f8dbf6f11d31d3de794d22e18098b23",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "281a226314238e8adb08d11b765347687ffb38b9",
                            "lessThan": "ead6680f354f83966c796fc7f9463a3171789616",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/dma-buf/dma-buf.c"
                    ],
                    "versions": [
                        {
                            "version": "7.0",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "7.0",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0.12",
                            "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": "7.0",
                                    "versionEndExcluding": "7.0.12"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "7.0",
                                    "versionEndExcluding": "7.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/b569f86e2f8dbf6f11d31d3de794d22e18098b23"
                },
                {
                    "url": "https://git.kernel.org/stable/c/ead6680f354f83966c796fc7f9463a3171789616"
                }
            ],
            "title": "dma-buf: fix UAF in dma_buf_fd() tracepoint",
            "x_generator": {
                "engine": "bippy-1.2.0"
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    }
}