CVE-2025-21696

{"id": "CVE-2025-21696", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"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"}, "impactScore": 3.6, "exploitabilityScore": 1.8}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"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"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2025-02-12T14:15:32.677", "references": [{"url": "https://git.kernel.org/stable/c/0cef0bb836e3cfe00f08f9606c72abd72fe78ca3", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/310ac886d68de661c3a334198d8604b722d7fdf8", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "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."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: mm: borrar el estado PTE/PMD de uffd-wp en mremap() Al borrar con mremap() una regi\u00f3n de memoria registrada previamente con userfaultfd como protegida contra escritura pero sin UFFD_FEATURE_EVENT_REMAP, una inconsistencia en la depuraci\u00f3n de indicadores provoca una falta de coincidencia entre los indicadores vma (que tienen uffd-wp borrado) y los indicadores pte/pmd (que no tienen uffd-wp borrado). Esta falta de coincidencia hace que un mprotect(PROT_WRITE) posterior active una advertencia en page_table_check_pte_flags() debido a la configuraci\u00f3n de pte como escribible mientras uffd-wp a\u00fan est\u00e1 configurado. Solucione esto borrando siempre expl\u00edcitamente los indicadores pte/pmd de uffd-wp en cualquier mremap() de este tipo para que los valores sean coherentes con la depuraci\u00f3n existente de VM_UFFD_WP. Tenga cuidado de borrar el indicador l\u00f3gico independientemente de su forma f\u00edsica: un bit PTE, un bit PTE de intercambio o un marcador PTE. Cubra las rutas PTE, PMD enormes y TLB enormes."}], "lastModified": "2025-10-01T20:18:21.500", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5D417CD4-B1C8-4FE8-8AF0-A83BA4A02112", "versionEndExcluding": "6.12.11", "versionStartIncluding": "5.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "62567B3C-6CEE-46D0-BC2E-B3717FBF7D13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5A073481-106D-4B15-B4C7-FB0213B8E1D4"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DE491969-75AE-4A6B-9A58-8FC5AF98798F"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "93C0660D-7FB8-4FBA-892A-B064BA71E49E"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "034C36A6-C481-41F3-AE9A-D116E5BE6895"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8AF9DC49-2085-4FFB-A7E3-73DFAFECC7F2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc7:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5DFCDFB8-4FD0-465A-9076-D813D78FE51B"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}