{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2025-40243", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-40243", "idYear": 2025, "status": "PUBLISHED", "publishedAt": "2025-12-04T15:31:32.422Z", "updatedAt": "2026-08-05T12:08:47.346Z", "importedAt": "2026-10-24T01:57:34.152Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "hfs: fix KMSAN uninit-value issue in hfs_find_set_zero_bits()", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nhfs: fix KMSAN uninit-value issue in hfs_find_set_zero_bits()\n\nThe syzbot reported issue in hfs_find_set_zero_bits():\n\n=====================================================\nBUG: KMSAN: uninit-value in hfs_find_set_zero_bits+0x74d/0xb60 fs/hfs/bitmap.c:45\n hfs_find_set_zero_bits+0x74d/0xb60 fs/hfs/bitmap.c:45\n hfs_vbm_search_free+0x13c/0x5b0 fs/hfs/bitmap.c:151\n hfs_extend_file+0x6a5/0x1b00 fs/hfs/extent.c:408\n hfs_get_block+0x435/0x1150 fs/hfs/extent.c:353\n __block_write_begin_int+0xa76/0x3030 fs/buffer.c:2151\n block_write_begin fs/buffer.c:2262 [inline]\n cont_write_begin+0x10e1/0x1bc0 fs/buffer.c:2601\n hfs_write_begin+0x85/0x130 fs/hfs/inode.c:52\n cont_expand_zero fs/buffer.c:2528 [inline]\n cont_write_begin+0x35a/0x1bc0 fs/buffer.c:2591\n hfs_write_begin+0x85/0x130 fs/hfs/inode.c:52\n hfs_file_truncate+0x1d6/0xe60 fs/hfs/extent.c:494\n hfs_inode_setattr+0x964/0xaa0 fs/hfs/inode.c:654\n notify_change+0x1993/0x1aa0 fs/attr.c:552\n do_truncate+0x28f/0x310 fs/open.c:68\n do_ftruncate+0x698/0x730 fs/open.c:195\n do_sys_ftruncate fs/open.c:210 [inline]\n __do_sys_ftruncate fs/open.c:215 [inline]\n __se_sys_ftruncate fs/open.c:213 [inline]\n __x64_sys_ftruncate+0x11b/0x250 fs/open.c:213\n x64_sys_call+0xfe3/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:78\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nUninit was created at:\n slab_post_alloc_hook mm/slub.c:4154 [inline]\n slab_alloc_node mm/slub.c:4197 [inline]\n __kmalloc_cache_noprof+0x7f7/0xed0 mm/slub.c:4354\n kmalloc_noprof include/linux/slab.h:905 [inline]\n hfs_mdb_get+0x1cc8/0x2a90 fs/hfs/mdb.c:175\n hfs_fill_super+0x3d0/0xb80 fs/hfs/super.c:337\n get_tree_bdev_flags+0x6e3/0x920 fs/super.c:1681\n get_tree_bdev+0x38/0x50 fs/super.c:1704\n hfs_get_tree+0x35/0x40 fs/hfs/super.c:388\n vfs_get_tree+0xb0/0x5c0 fs/super.c:1804\n do_new_mount+0x738/0x1610 fs/namespace.c:3902\n path_mount+0x6db/0x1e90 fs/namespace.c:4226\n do_mount fs/namespace.c:4239 [inline]\n __do_sys_mount fs/namespace.c:4450 [inline]\n __se_sys_mount+0x6eb/0x7d0 fs/namespace.c:4427\n __x64_sys_mount+0xe4/0x150 fs/namespace.c:4427\n x64_sys_call+0xfa7/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:166\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nCPU: 1 UID: 0 PID: 12609 Comm: syz.1.2692 Not tainted 6.16.0-syzkaller #0 PREEMPT(none)\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025\n=====================================================\n\nThe HFS_SB(sb)->bitmap buffer is allocated in hfs_mdb_get():\n\nHFS_SB(sb)->bitmap = kmalloc(8192, GFP_KERNEL);\n\nFinally, it can trigger the reported issue because kmalloc()\ndoesn't clear the allocated memory. If allocated memory contains\nonly zeros, then everything will work pretty fine.\nBut if the allocated memory contains the \"garbage\", then\nit can affect the bitmap operations and it triggers\nthe reported issue.\n\nThis patch simply exchanges the kmalloc() on kzalloc()\nwith the goal to guarantee the correctness of bitmap operations.\nBecause, newly created allocation bitmap should have all\navailable blocks free. Potentially, initialization bitmap's read\noperation could not fill the whole allocated memory and\n\"garbage\" in the not initialized memory will be the reason of\nvolume coruptions and file system driver bugs.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "fc56548fca732f3d3692c83b40db796259a03887" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "bf1683078fbdd09a7f7f9b74121ebaa03432bd00" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "2a112cdd66f5a132da5235ca31a320528c86bf33" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "e148ed5cda8fd96d4620c4622fb02f552a2d166a" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "cfafefcb0e1fc60135f7040f4aed0a4aef4f76ca" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "3b447fd401824e1ccf0b769188edefe866a1e676" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "502fa92a71f344611101bd04ef1a595b8b6014f5" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "2048ec5b98dbdfe0b929d2e42dc7a54c389c53dd" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "2.6.12", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "2.6.12" }, { "version": "5.4.301", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.4.*" }, { "version": "5.10.246", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.196", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.158", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.115", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.56", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.17.6", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.17.*" }, { "version": "6.18", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }