Answer in brief
CVE-2025-40044 records a Unknown severity vulnerability in fs: udf: fix OOB read in lengthAllocDescs handling. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2025-40044 records a Unknown severity vulnerability in fs: udf: fix OOB read in lengthAllocDescs handling. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <14496175b264d30c2045584ee31d062af2e3a660 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d2ed9aa8ae50fb0d4ac5ab07e4c67ba7e9a24818 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1d1847812a1a5375c10a2a779338df643f79c047 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <918649364fbca7d5df72522ca795479edcd25f91 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a70dcfa8d0a0cc530a6af59483dfca260b652c1b || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b57f2d7d3e6bb89ed82330c5fe106cdfa34d3e24 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <459404f858213967ccfff336c41747d8dd186d38 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3bd5e45c2ce30e239d596becd5db720f7eb83c99 | 14496175b264d30c2045584ee31d062af2e3a660, d2ed9aa8ae50fb0d4ac5ab07e4c67ba7e9a24818, 1d1847812a1a5375c10a2a779338df643f79c047, 918649364fbca7d5df72522ca795479edcd25f91, a70dcfa8d0a0cc530a6af59483dfca260b652c1b, b57f2d7d3e6bb89ed82330c5fe106cdfa34d3e24, 459404f858213967ccfff336c41747d8dd186d38, 3bd5e45c2ce30e239d596becd5db720f7eb83c99 |
| Linux/Linuxgeneric | 2.6.12 | Not reported |
Published upstream
Oct 28, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
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.
Quoted source text, attributed separately from HOL analysis.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <14496175b264d30c2045584ee31d062af2e3a660 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d2ed9aa8ae50fb0d4ac5ab07e4c67ba7e9a24818 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <1d1847812a1a5375c10a2a779338df643f79c047 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <918649364fbca7d5df72522ca795479edcd25f91 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a70dcfa8d0a0cc530a6af59483dfca260b652c1b || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b57f2d7d3e6bb89ed82330c5fe106cdfa34d3e24 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <459404f858213967ccfff336c41747d8dd186d38 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3bd5e45c2ce30e239d596becd5db720f7eb83c99 | 14496175b264d30c2045584ee31d062af2e3a660, d2ed9aa8ae50fb0d4ac5ab07e4c67ba7e9a24818, 1d1847812a1a5375c10a2a779338df643f79c047, 918649364fbca7d5df72522ca795479edcd25f91, a70dcfa8d0a0cc530a6af59483dfca260b652c1b, b57f2d7d3e6bb89ed82330c5fe106cdfa34d3e24, 459404f858213967ccfff336c41747d8dd186d38, 3bd5e45c2ce30e239d596becd5db720f7eb83c99 |
| Linux/Linuxgeneric | 2.6.12 | Not reported |
Published upstream
Oct 28, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
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.
Quoted source text, attributed separately from HOL analysis.