{"api_version":"1","generated_at":"2026-07-23T13:24:47+00:00","cve":"CVE-2026-64031","urls":{"html":"https://cve.report/CVE-2026-64031","api":"https://cve.report/api/cve/CVE-2026-64031.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64031","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64031"},"summary":{"title":"erofs: fix managed cache race for unaligned extents","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: fix managed cache race for unaligned extents\n\nAfter unaligned compressed extents were introduced, the following race\ncould occur:\n\n[Thread 1]                                   [Thread 2]\n(z_erofs_fill_bio_vec)\n<handle a Z_EROFS_PREALLOCATED_FOLIO folio>\n...\nfilemap_add_folio (1)\n                                             (z_erofs_bind_cache)\n                                             <the same folio is found..>\n                                             ..\n                                             ..\nfolio_attach_private (2)\n                                             filemap_add_folio (3) again\n\nSince (1) is executed but (2) hasn't been executed yet, it's possible\nthat another thread finds the same managed folio in z_erofs_bind_cache()\nfor a different pcluster and calls filemap_add_folio() again since\nfolio->private is still Z_EROFS_PREALLOCATED_FOLIO.\n\nFix this by explicitly clearing folio->private before making the folio\nvisible in the managed cache so that another pcluster can simply wait\non the locked managed folio as what we did for other shared cases [1].\n\nThis only impacts unaligned data compression (`-E48bit` with zstd,\nfor example).\n\n[1] Commit 9e2f9d34dd12 (\"erofs: handle overlapped pclusters out of\n crafted images properly\") was originally introduced to handle crafted\n overlapped extents, but it addresses unaligned extents as well.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-19 16:17:43","updated_at":"2026-07-20 15:17:03"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"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","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/649932fc3815eda2f24eb4de4b3a5e94886ee0b9","name":"https://git.kernel.org/stable/c/649932fc3815eda2f24eb4de4b3a5e94886ee0b9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/425d32d6288d7d845e486af9419bbedccd8c9103","name":"https://git.kernel.org/stable/c/425d32d6288d7d845e486af9419bbedccd8c9103","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/038166f873c4caf6e85cfd4ea0c5a5ba297b4e8b","name":"https://git.kernel.org/stable/c/038166f873c4caf6e85cfd4ea0c5a5ba297b4e8b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64031","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64031","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7361d1e3763baaf7b9349c576137851458ad38d1 425d32d6288d7d845e486af9419bbedccd8c9103 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7361d1e3763baaf7b9349c576137851458ad38d1 038166f873c4caf6e85cfd4ea0c5a5ba297b4e8b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7361d1e3763baaf7b9349c576137851458ad38d1 649932fc3815eda2f24eb4de4b3a5e94886ee0b9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.15","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.15 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.34 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.11 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"64031","cve":"CVE-2026-64031","epss":"0.001660000","percentile":"0.061580000","score_date":"2026-07-20","updated_at":"2026-07-21 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the Linux kernel, the following vulnerability has been resolved:\n\nerofs: fix managed cache race for unaligned extents\n\nAfter unaligned compressed extents were introduced, the following race\ncould occur:\n\n[Thread 1]                                   [Thread 2]\n(z_erofs_fill_bio_vec)\n<handle a Z_EROFS_PREALLOCATED_FOLIO folio>\n...\nfilemap_add_folio (1)\n                                             (z_erofs_bind_cache)\n                                             <the same folio is found..>\n                                             ..\n                                             ..\nfolio_attach_private (2)\n                                             filemap_add_folio (3) again\n\nSince (1) is executed but (2) hasn't been executed yet, it's possible\nthat another thread finds the same managed folio in z_erofs_bind_cache()\nfor a different pcluster and calls filemap_add_folio() again since\nfolio->private is still Z_EROFS_PREALLOCATED_FOLIO.\n\nFix this by explicitly clearing folio->private before making the folio\nvisible in the managed cache so that another pcluster can simply wait\non the locked managed folio as what we did for other shared cases [1].\n\nThis only impacts unaligned data compression (`-E48bit` with zstd,\nfor example).\n\n[1] Commit 9e2f9d34dd12 (\"erofs: handle overlapped pclusters out of\n crafted images properly\") was originally introduced to handle crafted\n overlapped extents, but it addresses unaligned extents as well."}],"metrics":[{"cvssV3_1":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-07-20T13:42:34.848Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/425d32d6288d7d845e486af9419bbedccd8c9103"},{"url":"https://git.kernel.org/stable/c/038166f873c4caf6e85cfd4ea0c5a5ba297b4e8b"},{"url":"https://git.kernel.org/stable/c/649932fc3815eda2f24eb4de4b3a5e94886ee0b9"}],"title":"erofs: fix managed cache race for unaligned extents","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-64031","datePublished":"2026-07-19T15:39:21.609Z","dateReserved":"2026-07-19T07:54:57.028Z","dateUpdated":"2026-07-20T13:42:34.848Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-19 16:17:43","lastModifiedDate":"2026-07-20 15:17:03","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"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","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64031","Ordinal":"1","Title":"erofs: fix managed cache race for unaligned extents","CVE":"CVE-2026-64031","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64031","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nerofs: fix managed cache race for unaligned extents\n\nAfter unaligned compressed extents were introduced, the following race\ncould occur:\n\n[Thread 1]                                   [Thread 2]\n(z_erofs_fill_bio_vec)\n<handle a Z_EROFS_PREALLOCATED_FOLIO folio>\n...\nfilemap_add_folio (1)\n                                             (z_erofs_bind_cache)\n                                             <the same folio is found..>\n                                             ..\n                                             ..\nfolio_attach_private (2)\n                                             filemap_add_folio (3) again\n\nSince (1) is executed but (2) hasn't been executed yet, it's possible\nthat another thread finds the same managed folio in z_erofs_bind_cache()\nfor a different pcluster and calls filemap_add_folio() again since\nfolio->private is still Z_EROFS_PREALLOCATED_FOLIO.\n\nFix this by explicitly clearing folio->private before making the folio\nvisible in the managed cache so that another pcluster can simply wait\non the locked managed folio as what we did for other shared cases [1].\n\nThis only impacts unaligned data compression (`-E48bit` with zstd,\nfor example).\n\n[1] Commit 9e2f9d34dd12 (\"erofs: handle overlapped pclusters out of\n crafted images properly\") was originally introduced to handle crafted\n overlapped extents, but it addresses unaligned extents as well.","Type":"Description","Title":"erofs: fix managed cache race for unaligned extents"}]}}}