{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-23432",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-01-13T15:37:46.016Z",
        "datePublished": "2026-04-03T15:15:18.061Z",
        "dateUpdated": "2026-08-05T12:21:43.430Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:21:43.430Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmshv: Fix use-after-free in mshv_map_user_memory error path\n\nIn the error path of mshv_map_user_memory(), calling vfree() directly on\nthe region leaves the MMU notifier registered. When userspace later unmaps\nthe memory, the notifier fires and accesses the freed region, causing a\nuse-after-free and potential kernel panic.\n\nReplace vfree() with mshv_partition_put() to properly unregister\nthe MMU notifier before freeing the region."
                }
            ],
            "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 vulnerable path is reached through local `/dev/mshv` and partition-file ioctls, specifically `MSHV_SET_GUEST_MEMORY`, not via network or adjacent protocols.\nAC:L - The attacker controls the memory-region parameters and can subsequently unmap the userspace range to fire the stale MMU notifier. No attacker-uncontrolled race or special victim state is required.\nPR:L - The attacker needs local access to the mshv device or an already-created partition fd, but the vulnerable ioctl itself has no `capable()` check. In a reasonable VMM deployment where that fd/device is granted to a service process, this is Low rather than High.\nUI:N - After obtaining the local mshv interface, the attacker can issue the ioctl and unmap memory without requiring any separate user action.\nS:U - The bug corrupts kernel memory through a kernel driver interface and impacts the same kernel security authority. This is not a guest-to-host escape path from inside a VM.\nC:H - This is a use-after-free of a registered MMU interval notifier embedded in `struct mshv_mem_region`. Reuse of the freed vmalloc object can plausibly expose kernel memory or support read primitives.\nI:H - The stale notifier callback dereferences and writes through fields of freed attacker-reclaimable kernel memory, including notifier sequence and region state. As a kernel UAF, it is plausibly exploitable for memory corruption or control-flow impact.\nA:H - The upstream fix explicitly notes that later userspace unmapping can fire the notifier on freed memory and cause a kernel panic. A local attacker can trigger this repeatedly for host denial of service."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/hv/mshv_root_main.c"
                    ],
                    "versions": [
                        {
                            "version": "b9a66cd5ccbb9fade15d0e427e19470d8ad35b75",
                            "lessThan": "34861bdc0c0196b6c2dd48f7454029407704ff6e",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "b9a66cd5ccbb9fade15d0e427e19470d8ad35b75",
                            "lessThan": "6922db250422a0dfee34de322f86b7a73d713d33",
                            "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/hv/mshv_root_main.c"
                    ],
                    "versions": [
                        {
                            "version": "6.19",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.19",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.19.10",
                            "lessThanOrEqual": "6.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0",
                            "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": "6.19",
                                    "versionEndExcluding": "6.19.10"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.19",
                                    "versionEndExcluding": "7.0"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/34861bdc0c0196b6c2dd48f7454029407704ff6e"
                },
                {
                    "url": "https://git.kernel.org/stable/c/6922db250422a0dfee34de322f86b7a73d713d33"
                }
            ],
            "title": "mshv: Fix use-after-free in mshv_map_user_memory error path",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}