CVE-2026-72203
Estado: RecibidaAlta (7.5)—
In the Linux kernel, the following vulnerability has been resolved:
ntfs: skip extent mft records in writeback to prevent deadlock
This patch fixes the ABBA deadlock between extent_lock and extent mrec_lock triggered by xfstests generic/113, that occurs since the commit 6994acf33bae ("ntfs: use base mft_no when looking up base inode for extent record").
By removing all extent_lock and extent mrec_lock acquisition from the MFT folio writeback path, the ABBA lock ordering is eliminated:
Path A: __ntfs_write_inode(): extent_lock -> mrec_lock Path B (removed): ntfs_write_mft_block(): mrec_lock -> extent_lock
Leer descripción completaMostrar menos
Path B is always redundant for extent records because:
Detalles técnicos trazas, registros y código del informe original
Path A (inode writeback):
VFS writeback
-> ntfs_write_inode()
-> __ntfs_write_inode()
-> mutex_lock(&ni->extent_lock)
-> mutex_lock(&tni->mrec_lock)
Path B (MFT folio writeback):
VFS writeback of $MFT dirty folios
-> ntfs_mft_writepages()
-> ntfs_write_mft_block()
-> ntfs_may_write_mft_record()
-> holds one extent mrec_lock from a previous iteration
-> tries to acquire another base inode extent_lock
1. mark_mft_record_dirty(ext_ni) does NOT dirty the MFT folio.
It only sets NInoDirty(ext_ni) and marks the base VFS inode dirty
via __mark_inode_dirty(I_DIRTY_DATASYNC), which triggers Path A.
Therefore, normal extent modifications never create a situation where
the MFT folio is dirty and Path B is not scheduled.
2. The MFT folio only gets dirtied via ntfs_mft_mark_dirty() inside
ntfs_mft_record_alloc(). But all identified callers in attrib.c
(ntfs_attr_add, ntfs_attr_record_move_away,
ntfs_attr_make_non_resident, ntfs_attr_record_resize) follow through
with mark_mft_record_dirty(), which triggers Path A to write the
complete record.
3. ntfs_evict_big_inode() calls ntfs_commit_inode() before freeing extent
inodes, ensuring all dirty extents are flushed via Path A before the
base inode leaves the icache.CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.61%
- Percentil entre todas las CVEs puntuadas: 47
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access60 % - Impacto principal
T1499Endpoint Denial of Serviceimpact55 %
Inferido por reglas deterministas a partir del vector CVSS y la CWE. Solo orientativo.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-72203",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Secondary",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"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": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "7ffa8f3d30236e0ab897c30bdb01224ff1fe1c89",
"versionType": "git"
},
{
"status": "affected",
"version": "1e9ea7e04472d4e5e12e58c881eaacfb3e49b669",
"lessThan": "f831ab09d521898bf1dd99bf5adfd630ea1428e3",
"versionType": "git"
},
{
"status": "affected",
"version": "1e9ea7e04472d4e5e12e58c881eaacfb3e49b669",
"lessThan": "76bc14c7097ff678b2b5dbfd4fa33b46897d87ce",
"versionType": "git"
}
],
"programFiles": [
"fs/ntfs/mft.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.12"
},
{
"status": "affected",
"version": "7.1"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.9",
"lessThan": "7.1",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"fs/ntfs/mft.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-08-15T06:21:38.970",
"references": [
{
"url": "https://git.kernel.org/stable/c/76bc14c7097ff678b2b5dbfd4fa33b46897d87ce",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/7ffa8f3d30236e0ab897c30bdb01224ff1fe1c89",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f831ab09d521898bf1dd99bf5adfd630ea1428e3",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nntfs: skip extent mft records in writeback to prevent deadlock\n\nThis patch fixes the ABBA deadlock between extent_lock and extent\nmrec_lock triggered by xfstests generic/113, that occurs since the commit\n6994acf33bae (\"ntfs: use base mft_no when looking up base inode for\n\t\textent record\").\n\nPath A (inode writeback):\n VFS writeback\n -> ntfs_write_inode()\n -> __ntfs_write_inode()\n -> mutex_lock(&ni->extent_lock)\n -> mutex_lock(&tni->mrec_lock)\n\nPath B (MFT folio writeback):\n VFS writeback of $MFT dirty folios\n -> ntfs_mft_writepages()\n -> ntfs_write_mft_block()\n -> ntfs_may_write_mft_record()\n -> holds one extent mrec_lock from a previous iteration\n -> tries to acquire another base inode extent_lock\n\nBy removing all extent_lock and extent mrec_lock acquisition from the MFT\nfolio writeback path, the ABBA lock ordering is eliminated:\n\nPath A: __ntfs_write_inode(): extent_lock -> mrec_lock\nPath B (removed): ntfs_write_mft_block(): mrec_lock -> extent_lock\n\nPath B is always redundant for extent records because:\n\n1. mark_mft_record_dirty(ext_ni) does NOT dirty the MFT folio.\n It only sets NInoDirty(ext_ni) and marks the base VFS inode dirty\n via __mark_inode_dirty(I_DIRTY_DATASYNC), which triggers Path A.\n Therefore, normal extent modifications never create a situation where\n the MFT folio is dirty and Path B is not scheduled.\n\n2. The MFT folio only gets dirtied via ntfs_mft_mark_dirty() inside\n ntfs_mft_record_alloc(). But all identified callers in attrib.c\n (ntfs_attr_add, ntfs_attr_record_move_away,\n ntfs_attr_make_non_resident, ntfs_attr_record_resize) follow through\n with mark_mft_record_dirty(), which triggers Path A to write the\n complete record.\n\n3. ntfs_evict_big_inode() calls ntfs_commit_inode() before freeing extent\n inodes, ensuring all dirty extents are flushed via Path A before the\n base inode leaves the icache."
}
],
"lastModified": "2026-08-19T08:17:13.473",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}