CVE-2025-71159

{"id": "CVE-2025-71159", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}, {"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "e8513c012de75fd65e2df5499572bc6ef3f6e409", "lessThan": "c8385851a5435f4006281828d428e5d0b0bbf8af", "versionType": "git"}, {"status": "affected", "version": "e8513c012de75fd65e2df5499572bc6ef3f6e409", "lessThan": "83f59076a1ae6f5c6845d6f7ed3a1a373d883684", "versionType": "git"}], "programFiles": ["fs/btrfs/delayed-inode.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.18"}, {"status": "unaffected", "version": "0", "lessThan": "6.18", "versionType": "semver"}, {"status": "unaffected", "version": "6.18.6", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "6.19", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["fs/btrfs/delayed-inode.c"], "defaultStatus": "affected"}]}], "published": "2026-01-23T16:15:52.793", "references": [{"url": "https://git.kernel.org/stable/c/83f59076a1ae6f5c6845d6f7ed3a1a373d883684", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c8385851a5435f4006281828d428e5d0b0bbf8af", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-416"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix use-after-free warning in btrfs_get_or_create_delayed_node()\n\nPreviously, btrfs_get_or_create_delayed_node() set the delayed_node's\nrefcount before acquiring the root->delayed_nodes lock.\nCommit e8513c012de7 (\"btrfs: implement ref_tracker for delayed_nodes\")\nmoved refcount_set inside the critical section, which means there is\nno longer a memory barrier between setting the refcount and setting\nbtrfs_inode->delayed_node.\n\nWithout that barrier, the stores to node->refs and\nbtrfs_inode->delayed_node may become visible out of order. Another\nthread can then read btrfs_inode->delayed_node and attempt to\nincrement a refcount that hasn't been set yet, leading to a\nrefcounting bug and a use-after-free warning.\n\nThe fix is to move refcount_set back to where it was to take\nadvantage of the implicit memory barrier provided by lock\nacquisition.\n\nBecause the allocations now happen outside of the lock's critical\nsection, they can use GFP_NOFS instead of GFP_ATOMIC."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nbtrfs: soluciona la advertencia de uso despu\u00e9s de liberaci\u00f3n en btrfs_get_or_create_delayed_node()\n\nAnteriormente, btrfs_get_or_create_delayed_node() establec\u00eda el refcount del delayed_node antes de adquirir el bloqueo root->delayed_nodes. El commit e8513c012de7 ('btrfs: implementa ref_tracker para delayed_nodes') movi\u00f3 refcount_set dentro de la secci\u00f3n cr\u00edtica, lo que significa que ya no hay una barrera de memoria entre el establecimiento del refcount y el establecimiento de btrfs_inode->delayed_node.\n\nSin esa barrera, los almacenamientos en node->refs y btrfs_inode->delayed_node pueden volverse visibles fuera de orden. Otro hilo puede entonces leer btrfs_inode->delayed_node e intentar incrementar un refcount que a\u00fan no ha sido establecido, lo que lleva a un error de refcounting y a una advertencia de uso despu\u00e9s de liberaci\u00f3n.\n\nLa soluci\u00f3n es mover refcount_set de vuelta a donde estaba para aprovechar la barrera de memoria impl\u00edcita proporcionada por la adquisici\u00f3n del bloqueo.\n\nDebido a que las asignaciones ahora ocurren fuera de la secci\u00f3n cr\u00edtica del bloqueo, pueden usar GFP_NOFS en lugar de GFP_ATOMIC."}], "lastModified": "2026-07-30T06:24:54.993", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B263F4AD-C03D-4E6A-995E-B822989C3A7A", "versionEndExcluding": "6.18.6", "versionStartIncluding": "6.18"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "17B67AA7-40D6-4AFA-8459-F200F3D7CFD1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C47E4CC9-C826-4FA9-B014-7FE3D9B318B2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F71D92C0-C023-48BD-B3B6-70B638EEE298"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "13580667-0A98-40CC-B29F-D12790B91BDB"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}