CVE-2025-40044
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: fs: udf: fix OOB read in lengthAllocDescs handling When parsing Allocation Extent Descriptor, lengthAllocDescs comes from on-disk data and must be validated against the block size. Crafted or corrupted images may set lengthAllocDescs so that the total descriptor length (sizeof(allocExtDesc) + lengthAllocDescs) exceeds the buffer, leading udf_update_tag() to call crc_itu_t() on out-of-bounds memory and trigger a KASAN use-after-free read. BUG: KASAN: use-after-free in crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60 Read of size 1 at addr ffff888041e7d000 by task syz-executor317/5309 CPU: 0 UID: 0 PID: 5309 Comm: syz-executor317 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60 udf_update_tag+0x70/0x6a0 fs/udf/misc.c:261 udf_write_aext+0x4d8/0x7b0 fs/udf/inode.c:2179 extent_trunc+0x2f7/0x4a0 fs/udf/truncate.c:46 udf_truncate_tail_extent+0x527/0x7e0 fs/udf/truncate.c:106 udf_release_file+0xc1/0x120 fs/udf/file.c:185 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:939 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 __do_sys_exit_group kernel/exit.c:1099 [inline] __se_sys_exit_group kernel/exit.c:1097 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Validate the computed total length against epos->bh->b_size. Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Severity
HIGH
CVSS score
7.8
(v3.1)
Vulnerability status
Deferred
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-10-28 12:15:38.453000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON
{
"id": "CVE-2025-40044",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-10-28T12:15:38.453",
"lastModified": "2026-10-19T21:10:00.160",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs: udf: fix OOB read in lengthAllocDescs handling\n\nWhen parsing Allocation Extent Descriptor, lengthAllocDescs comes from\non-disk data and must be validated against the block size. Crafted or\ncorrupted images may set lengthAllocDescs so that the total descriptor\nlength (sizeof(allocExtDesc) + lengthAllocDescs) exceeds the buffer,\nleading udf_update_tag() to call crc_itu_t() on out-of-bounds memory and\ntrigger a KASAN use-after-free read.\n\nBUG: KASAN: use-after-free in crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60\nRead of size 1 at addr ffff888041e7d000 by task syz-executor317/5309\n\nCPU: 0 UID: 0 PID: 5309 Comm: syz-executor317 Not tainted 6.12.0-rc4-syzkaller-00261-g850925a8133c #0\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014\nCall Trace:\n <TASK>\n __dump_stack lib/dump_stack.c:94 [inline]\n dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120\n print_address_description mm/kasan/report.c:377 [inline]\n print_report+0x169/0x550 mm/kasan/report.c:488\n kasan_report+0x143/0x180 mm/kasan/report.c:601\n crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60\n udf_update_tag+0x70/0x6a0 fs/udf/misc.c:261\n udf_write_aext+0x4d8/0x7b0 fs/udf/inode.c:2179\n extent_trunc+0x2f7/0x4a0 fs/udf/truncate.c:46\n udf_truncate_tail_extent+0x527/0x7e0 fs/udf/truncate.c:106\n udf_release_file+0xc1/0x120 fs/udf/file.c:185\n __fput+0x23f/0x880 fs/file_table.c:431\n task_work_run+0x24f/0x310 kernel/task_work.c:239\n exit_task_work include/linux/task_work.h:43 [inline]\n do_exit+0xa2f/0x28e0 kernel/exit.c:939\n do_group_exit+0x207/0x2c0 kernel/exit.c:1088\n __do_sys_exit_group kernel/exit.c:1099 [inline]\n __se_sys_exit_group kernel/exit.c:1097 [inline]\n __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097\n x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n </TASK>\n\nValidate the computed total length against epos->bh->b_size.\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nfs: udf: corrige lectura fuera de límites en el manejo de lengthAllocDescs\n\nAl analizar el Descriptor de Extensión de Asignación, lengthAllocDescs proviene de\ndatos en disco y debe ser validado contra el tamaño del bloque. Imágenes manipuladas o\ncorruptas pueden establecer lengthAllocDescs de modo que la longitud total del descriptor\n(sizeof(allocExtDesc) + lengthAllocDescs) exceda el búfer,\nllevando a udf_update_tag() a llamar a crc_itu_t() en memoria fuera de límites y\na activar una lectura de uso después de liberación de KASAN.\n\nERROR: KASAN: uso después de liberación en crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60\nLectura de tamaño 1 en la dirección ffff888041e7d000 por la tarea syz-executor317/5309\n\nCPU: 0 UID: 0 PID: 5309 Comm: syz-executor317 No contaminado 6.12.0-rc4-syzkaller-00261-g850925a8133c #0\nNombre del hardware: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014\nRastro de Llamada:\n <TAREA>\n __dump_stack lib/dump_stack.c:94 [inline]\n dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120\n print_address_description mm/kasan/report.c:377 [inline]\n print_report+0x169/0x550 mm/kasan/report.c:488\n kasan_report+0x143/0x180 mm/kasan/report.c:601\n crc_itu_t+0x1d5/0x2b0 lib/crc-itu-t.c:60\n udf_update_tag+0x70/0x6a0 fs/udf/misc.c:261\n udf_write_aext+0x4d8/0x7b0 fs/udf/inode.c:2179\n extent_trunc+0x2f7/0x4a0 fs/udf/truncate.c:46\n udf_truncate_tail_extent+0x527/0x7e0 fs/udf/truncate.c:106\n udf_release_file+0xc1/0x120 fs/udf/file.c:185\n __fput+0x23f/0x880 fs/file_table.c:431\n task_work_run+0x24f/0x310 kernel/task_work.c:239\n exit_task_work include/linux/task_work.h:43 [inline]\n do_exit+0xa2f/0x28e0 kernel/exit.c:939\n do_group_exit+0x207/0x2c0 kernel/exit.c:1088\n __do_sys_exit_group kernel/exit.c:1099 [inline]\n __se_sys_exit_group kernel/exit.c:1097 [inline]\n __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097\n x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n </TAREA>\n\nValidar la longitud total calculada contra epos->bh->b_size.\n\nEncontrado por el Centro de Verificación de Linux (linuxtesting.org) con Syzkaller."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"fs/udf/inode.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "14496175b264d30c2045584ee31d062af2e3a660",
"versionType": "git",
"status": "affected"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "d2ed9aa8ae50fb0d4ac5ab07e4c67ba7e9a24818",
"versionType": "git",
"status": "affected"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "1d1847812a1a5375c10a2a779338df643f79c047",
"versionType": "git",
"status": "affected"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "918649364fbca7d5df72522ca795479edcd25f91",
"versionType": "git",
"status": "affected"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "a70dcfa8d0a0cc530a6af59483dfca260b652c1b",
"versionType": "git",
"status": "affected"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "b57f2d7d3e6bb89ed82330c5fe106cdfa34d3e24",
"versionType": "git",
"status": "affected"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "459404f858213967ccfff336c41747d8dd186d38",
"versionType": "git",
"status": "affected"
},
{
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "3bd5e45c2ce30e239d596becd5db720f7eb83c99",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"fs/udf/inode.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "2.6.12",
"status": "affected"
},
{
"version": "0",
"lessThan": "2.6.12",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.4.301",
"lessThanOrEqual": "5.4.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.10.246",
"lessThanOrEqual": "5.10.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "5.15.195",
"lessThanOrEqual": "5.15.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.1.156",
"lessThanOrEqual": "6.1.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.112",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.53",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.17.3",
"lessThanOrEqual": "6.17.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-10-15T21:56:23.726969Z",
"id": "CVE-2025-40044",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"references": [
{
"url": "https://git.kernel.org/stable/c/14496175b264d30c2045584ee31d062af2e3a660",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/1d1847812a1a5375c10a2a779338df643f79c047",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/3bd5e45c2ce30e239d596becd5db720f7eb83c99",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/459404f858213967ccfff336c41747d8dd186d38",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/918649364fbca7d5df72522ca795479edcd25f91",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/a70dcfa8d0a0cc530a6af59483dfca260b652c1b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
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{
"url": "https://git.kernel.org/stable/c/b57f2d7d3e6bb89ed82330c5fe106cdfa34d3e24",
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{
"url": "https://git.kernel.org/stable/c/d2ed9aa8ae50fb0d4ac5ab07e4c67ba7e9a24818",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}