ghsa-4j58-87g3-fv33
Vulnerability from github
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: __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
Validate the computed total length against epos->bh->b_size.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
{
"affected": [],
"aliases": [
"CVE-2025-40044"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-10-28T12:15:38Z",
"severity": null
},
"details": "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 \u003cTASK\u003e\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 \u003c/TASK\u003e\n\nValidate the computed total length against epos-\u003ebh-\u003eb_size.\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller.",
"id": "GHSA-4j58-87g3-fv33",
"modified": "2025-10-29T15:31:53Z",
"published": "2025-10-28T12:30:16Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-40044"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/14496175b264d30c2045584ee31d062af2e3a660"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1d1847812a1a5375c10a2a779338df643f79c047"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3bd5e45c2ce30e239d596becd5db720f7eb83c99"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/459404f858213967ccfff336c41747d8dd186d38"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/918649364fbca7d5df72522ca795479edcd25f91"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/a70dcfa8d0a0cc530a6af59483dfca260b652c1b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b57f2d7d3e6bb89ed82330c5fe106cdfa34d3e24"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d2ed9aa8ae50fb0d4ac5ab07e4c67ba7e9a24818"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
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