CVE-2025-39866
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: fs: writeback: fix use-after-free in __mark_inode_dirty() An use-after-free issue occurred when __mark_inode_dirty() get the bdi_writeback that was in the progress of switching. CPU: 1 PID: 562 Comm: systemd-random- Not tainted 6.6.56-gb4403bd46a8e #1 ...... pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __mark_inode_dirty+0x124/0x418 lr : __mark_inode_dirty+0x118/0x418 sp : ffffffc08c9dbbc0 ........ Call trace: __mark_inode_dirty+0x124/0x418 generic_update_time+0x4c/0x60 file_modified+0xcc/0xd0 ext4_buffered_write_iter+0x58/0x124 ext4_file_write_iter+0x54/0x704 vfs_write+0x1c0/0x308 ksys_write+0x74/0x10c __arm64_sys_write+0x1c/0x28 invoke_syscall+0x48/0x114 el0_svc_common.constprop.0+0xc0/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x40/0xe4 el0t_64_sync_handler+0x120/0x12c el0t_64_sync+0x194/0x198 Root cause is: systemd-random-seed kworker ---------------------------------------------------------------------- ___mark_inode_dirty inode_switch_wbs_work_fn spin_lock(&inode->i_lock); inode_attach_wb locked_inode_to_wb_and_lock_list get inode->i_wb spin_unlock(&inode->i_lock); spin_lock(&wb->list_lock) spin_lock(&inode->i_lock) inode_io_list_move_locked spin_unlock(&wb->list_lock) spin_unlock(&inode->i_lock) spin_lock(&old_wb->list_lock) inode_do_switch_wbs spin_lock(&inode->i_lock) inode->i_wb = new_wb spin_unlock(&inode->i_lock) spin_unlock(&old_wb->list_lock) wb_put_many(old_wb, nr_switched) cgwb_release old wb released wb_wakeup_delayed() accesses wb, then trigger the use-after-free issue Fix this race condition by holding inode spinlock until wb_wakeup_delayed() finished.
Severity
HIGH
CVSS score
7.8
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-09-19 16:15:45.657000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON
{
"id": "CVE-2025-39866",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-09-19T16:15:45.657",
"lastModified": "2026-10-19T21:10:00.160",
"vulnStatus": "Modified",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs: writeback: fix use-after-free in __mark_inode_dirty()\n\nAn use-after-free issue occurred when __mark_inode_dirty() get the\nbdi_writeback that was in the progress of switching.\n\nCPU: 1 PID: 562 Comm: systemd-random- Not tainted 6.6.56-gb4403bd46a8e #1\n......\npstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\npc : __mark_inode_dirty+0x124/0x418\nlr : __mark_inode_dirty+0x118/0x418\nsp : ffffffc08c9dbbc0\n........\nCall trace:\n __mark_inode_dirty+0x124/0x418\n generic_update_time+0x4c/0x60\n file_modified+0xcc/0xd0\n ext4_buffered_write_iter+0x58/0x124\n ext4_file_write_iter+0x54/0x704\n vfs_write+0x1c0/0x308\n ksys_write+0x74/0x10c\n __arm64_sys_write+0x1c/0x28\n invoke_syscall+0x48/0x114\n el0_svc_common.constprop.0+0xc0/0xe0\n do_el0_svc+0x1c/0x28\n el0_svc+0x40/0xe4\n el0t_64_sync_handler+0x120/0x12c\n el0t_64_sync+0x194/0x198\n\nRoot cause is:\n\nsystemd-random-seed kworker\n----------------------------------------------------------------------\n___mark_inode_dirty inode_switch_wbs_work_fn\n\n spin_lock(&inode->i_lock);\n inode_attach_wb\n locked_inode_to_wb_and_lock_list\n get inode->i_wb\n spin_unlock(&inode->i_lock);\n spin_lock(&wb->list_lock)\n spin_lock(&inode->i_lock)\n inode_io_list_move_locked\n spin_unlock(&wb->list_lock)\n spin_unlock(&inode->i_lock)\n spin_lock(&old_wb->list_lock)\n inode_do_switch_wbs\n spin_lock(&inode->i_lock)\n inode->i_wb = new_wb\n spin_unlock(&inode->i_lock)\n spin_unlock(&old_wb->list_lock)\n wb_put_many(old_wb, nr_switched)\n cgwb_release\n old wb released\n wb_wakeup_delayed() accesses wb,\n then trigger the use-after-free\n issue\n\nFix this race condition by holding inode spinlock until\nwb_wakeup_delayed() finished."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nfs: writeback: corrige uso después de liberación en __mark_inode_dirty()\n\nSe produjo un problema de uso después de liberación cuando __mark_inode_dirty() obtiene el bdi_writeback que estaba en proceso de cambio.\n\nCPU: 1 PID: 562 Comm: systemd-random- No contaminado 6.6.56-gb4403bd46a8e #1\n......\npstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\npc : __mark_inode_dirty+0x124/0x418\nlr : __mark_inode_dirty+0x118/0x418\nsp : ffffffc08c9dbbc0\n........\nTraza de llamada:\n __mark_inode_dirty+0x124/0x418\n generic_update_time+0x4c/0x60\n file_modified+0xcc/0xd0\n ext4_buffered_write_iter+0x58/0x124\n ext4_file_write_iter+0x54/0x704\n vfs_write+0x1c0/0x308\n ksys_write+0x74/0x10c\n __arm64_sys_write+0x1c/0x28\n invoke_syscall+0x48/0x114\n el0_svc_common.constprop.0+0xc0/0xe0\n do_el0_svc+0x1c/0x28\n el0_svc+0x40/0xe4\n el0t_64_sync_handler+0x120/0x12c\n el0t_64_sync+0x194/0x198\n\nLa causa raíz es:\n\nsystemd-random-seed kworker\n----------------------------------------------------------------------\n___mark_inode_dirty inode_switch_wbs_work_fn\n\n spin_lock(&inode->i_lock);\n inode_attach_wb\n locked_inode_to_wb_and_lock_list\n obtiene inode->i_wb\n spin_unlock(&inode->i_lock);\n spin_lock(&wb->list_lock)\n spin_lock(&inode->i_lock)\n inode_io_list_move_locked\n spin_unlock(&wb->list_lock)\n spin_unlock(&inode->i_lock)\n spin_lock(&old_wb->list_lock)\n inode_do_switch_wbs\n spin_lock(&inode->i_lock)\n inode->i_wb = new_wb\n spin_unlock(&inode->i_lock)\n spin_unlock(&old_wb->list_lock)\n wb_put_many(old_wb, nr_switched)\n cgwb_release\n old wb liberado\n wb_wakeup_delayed() accede a wb,\n luego activa el uso después de liberación\n problema\n\nCorrige esta condición de carrera manteniendo el spinlock del inodo hasta que wb_wakeup_delayed() finalice."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"fs/fs-writeback.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "0747259d13febfcc838980a63c414c9b920cea6f",
"lessThan": "e2a14bbae5d8bacaa301362744a110e2be40a3a3",
"versionType": "git",
"status": "affected"
},
{
"version": "0747259d13febfcc838980a63c414c9b920cea6f",
"lessThan": "b187c976111960e6e54a6b1fff724f6e3d39406c",
"versionType": "git",
"status": "affected"
},
{
"version": "0747259d13febfcc838980a63c414c9b920cea6f",
"lessThan": "1edc2feb9c759a9883dfe81cb5ed231412d8b2e4",
"versionType": "git",
"status": "affected"
},
{
"version": "0747259d13febfcc838980a63c414c9b920cea6f",
"lessThan": "bf89b1f87c72df79cf76203f71fbf8349cd5c9de",
"versionType": "git",
"status": "affected"
},
{
"version": "0747259d13febfcc838980a63c414c9b920cea6f",
"lessThan": "e63052921f1b25a836feb1500b841bff7a4a0456",
"versionType": "git",
"status": "affected"
},
{
"version": "0747259d13febfcc838980a63c414c9b920cea6f",
"lessThan": "c8c14adf80bd1a6e4a1d7ee9c2a816881c26d17a",
"versionType": "git",
"status": "affected"
},
{
"version": "0747259d13febfcc838980a63c414c9b920cea6f",
"lessThan": "d02d2c98d25793902f65803ab853b592c7a96b29",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"fs/fs-writeback.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "4.2",
"status": "affected"
},
{
"version": "0",
"lessThan": "4.2",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.10.247",
"lessThanOrEqual": "5.10.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.192",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.151",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.105",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.46",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.16.6",
"lessThanOrEqual": "6.16.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.17",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"affectedData": [
{
"vendor": "Siemens",
"product": "SIMATIC CN 4100",
"defaultStatus": "unknown",
"versions": [
{
"version": "0",
"lessThan": "V5.0",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.5",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.5",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.5",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.5",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.5",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
},
{
"vendor": "Siemens",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"defaultStatus": "unknown",
"versions": [
{
"version": "V3.1.7",
"lessThan": "*",
"versionType": "custom",
"status": "affected"
}
]
}
]
}
],
"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
},
{
"source": "[email protected]",
"type": "Primary",
"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
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-15T21:54:28.454479Z",
"id": "CVE-2025-39866",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "CWE-416"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "4.2",
"versionEndExcluding": "5.10.247",
"matchCriteriaId": "973B2007-ACEA-4C4E-9A34-FF155EE17424"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.11",
"versionEndExcluding": "5.15.192",
"matchCriteriaId": "8A911BD7-361F-45C0-A4A6-33FCBA0F6117"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.16",
"versionEndExcluding": "6.1.151",
"matchCriteriaId": "BC2D0B88-F133-4143-B91D-0A439AA143C0"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.2",
"versionEndExcluding": "6.6.105",
"matchCriteriaId": "B9364B0C-6B18-422E-8254-73EF0E856875"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.7",
"versionEndExcluding": "6.12.46",
"matchCriteriaId": "F7E2B332-E920-4CAC-B400-288602DB6F16"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.13",
"versionEndExcluding": "6.16.6",
"matchCriteriaId": "548F104C-0F08-438B-9C97-64C903F0C678"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*",
"matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc2:*:*:*:*:*:*",
"matchCriteriaId": "C730CD9A-D969-4A8E-9522-162AAF7C0EE9"
}
]
}
]
},
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*",
"matchCriteriaId": "FA6FEEC2-9F11-4643-8827-749718254FED"
}
]
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/1edc2feb9c759a9883dfe81cb5ed231412d8b2e4",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://git.kernel.org/stable/c/b187c976111960e6e54a6b1fff724f6e3d39406c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://git.kernel.org/stable/c/bf89b1f87c72df79cf76203f71fbf8349cd5c9de",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://git.kernel.org/stable/c/c8c14adf80bd1a6e4a1d7ee9c2a816881c26d17a",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://git.kernel.org/stable/c/d02d2c98d25793902f65803ab853b592c7a96b29",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://git.kernel.org/stable/c/e2a14bbae5d8bacaa301362744a110e2be40a3a3",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://git.kernel.org/stable/c/e63052921f1b25a836feb1500b841bff7a4a0456",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
]
},
{
"url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html",
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
]
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-032379.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-457936.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
}
]
}