{"id":"AZL-68843","summary":"CVE-2025-40044 affecting package kernel for versions less than 6.6.112.1-2","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.","modified":"2026-04-01T05:21:29.595335Z","published":"2025-10-28T12:15:38Z","upstream":["CVE-2025-40044"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-40044"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.112.1-2"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-68843.json"}}],"schema_version":"1.7.5"}