{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-21696",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-12-29T08:45:45.743Z",
        "datePublished": "2025-02-12T13:27:54.905Z",
        "dateUpdated": "2026-05-11T21:04:39.524Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-05-11T21:04:39.524Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: clear uffd-wp PTE/PMD state on mremap()\n\nWhen mremap()ing a memory region previously registered with userfaultfd as\nwrite-protected but without UFFD_FEATURE_EVENT_REMAP, an inconsistency in\nflag clearing leads to a mismatch between the vma flags (which have\nuffd-wp cleared) and the pte/pmd flags (which do not have uffd-wp\ncleared).  This mismatch causes a subsequent mprotect(PROT_WRITE) to\ntrigger a warning in page_table_check_pte_flags() due to setting the pte\nto writable while uffd-wp is still set.\n\nFix this by always explicitly clearing the uffd-wp pte/pmd flags on any\nsuch mremap() so that the values are consistent with the existing clearing\nof VM_UFFD_WP.  Be careful to clear the logical flag regardless of its\nphysical form; a PTE bit, a swap PTE bit, or a PTE marker.  Cover PTE,\nhuge PMD and hugetlb paths."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/linux/userfaultfd_k.h",
                        "mm/huge_memory.c",
                        "mm/hugetlb.c",
                        "mm/mremap.c"
                    ],
                    "versions": [
                        {
                            "version": "63b2d4174c4ad1f40b48d7138e71bcb564c1fe03",
                            "lessThan": "310ac886d68de661c3a334198d8604b722d7fdf8",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "63b2d4174c4ad1f40b48d7138e71bcb564c1fe03",
                            "lessThan": "0cef0bb836e3cfe00f08f9606c72abd72fe78ca3",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/linux/userfaultfd_k.h",
                        "mm/huge_memory.c",
                        "mm/hugetlb.c",
                        "mm/mremap.c"
                    ],
                    "versions": [
                        {
                            "version": "5.7",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.7",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.11",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.13",
                            "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": "5.7",
                                    "versionEndExcluding": "6.12.11"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.7",
                                    "versionEndExcluding": "6.13"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/310ac886d68de661c3a334198d8604b722d7fdf8"
                },
                {
                    "url": "https://git.kernel.org/stable/c/0cef0bb836e3cfe00f08f9606c72abd72fe78ca3"
                }
            ],
            "title": "mm: clear uffd-wp PTE/PMD state on mremap()",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "cvssV3_1": {
                            "scope": "UNCHANGED",
                            "version": "3.1",
                            "baseScore": 5.5,
                            "attackVector": "LOCAL",
                            "baseSeverity": "MEDIUM",
                            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                            "integrityImpact": "NONE",
                            "userInteraction": "NONE",
                            "attackComplexity": "LOW",
                            "availabilityImpact": "HIGH",
                            "privilegesRequired": "LOW",
                            "confidentialityImpact": "NONE"
                        }
                    },
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2025-21696",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "version": "2.0.3",
                                "timestamp": "2025-10-01T19:51:14.846865Z"
                            }
                        }
                    }
                ],
                "problemTypes": [
                    {
                        "descriptions": [
                            {
                                "lang": "en",
                                "type": "CWE",
                                "description": "CWE-noinfo Not enough information"
                            }
                        ]
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2025-10-01T19:57:09.649Z"
                }
            }
        ]
    }
}