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CVE-2025-40244 (GCVE-0-2025-40244)

Vulnerability from cvelistv5 – Published: 2025-12-04 15:31 – Updated: 2026-08-05 12:08
VLAI
Title
hfsplus: fix KMSAN uninit-value issue in __hfsplus_ext_cache_extent()
Summary
In the Linux kernel, the following vulnerability has been resolved: hfsplus: fix KMSAN uninit-value issue in __hfsplus_ext_cache_extent() The syzbot reported issue in __hfsplus_ext_cache_extent(): [ 70.194323][ T9350] BUG: KMSAN: uninit-value in __hfsplus_ext_cache_extent+0x7d0/0x990 [ 70.195022][ T9350] __hfsplus_ext_cache_extent+0x7d0/0x990 [ 70.195530][ T9350] hfsplus_file_extend+0x74f/0x1cf0 [ 70.195998][ T9350] hfsplus_get_block+0xe16/0x17b0 [ 70.196458][ T9350] __block_write_begin_int+0x962/0x2ce0 [ 70.196959][ T9350] cont_write_begin+0x1000/0x1950 [ 70.197416][ T9350] hfsplus_write_begin+0x85/0x130 [ 70.197873][ T9350] generic_perform_write+0x3e8/0x1060 [ 70.198374][ T9350] __generic_file_write_iter+0x215/0x460 [ 70.198892][ T9350] generic_file_write_iter+0x109/0x5e0 [ 70.199393][ T9350] vfs_write+0xb0f/0x14e0 [ 70.199771][ T9350] ksys_write+0x23e/0x490 [ 70.200149][ T9350] __x64_sys_write+0x97/0xf0 [ 70.200570][ T9350] x64_sys_call+0x3015/0x3cf0 [ 70.201065][ T9350] do_syscall_64+0xd9/0x1d0 [ 70.201506][ T9350] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 70.202054][ T9350] [ 70.202279][ T9350] Uninit was created at: [ 70.202693][ T9350] __kmalloc_noprof+0x621/0xf80 [ 70.203149][ T9350] hfsplus_find_init+0x8d/0x1d0 [ 70.203602][ T9350] hfsplus_file_extend+0x6ca/0x1cf0 [ 70.204087][ T9350] hfsplus_get_block+0xe16/0x17b0 [ 70.204561][ T9350] __block_write_begin_int+0x962/0x2ce0 [ 70.205074][ T9350] cont_write_begin+0x1000/0x1950 [ 70.205547][ T9350] hfsplus_write_begin+0x85/0x130 [ 70.206017][ T9350] generic_perform_write+0x3e8/0x1060 [ 70.206519][ T9350] __generic_file_write_iter+0x215/0x460 [ 70.207042][ T9350] generic_file_write_iter+0x109/0x5e0 [ 70.207552][ T9350] vfs_write+0xb0f/0x14e0 [ 70.207961][ T9350] ksys_write+0x23e/0x490 [ 70.208375][ T9350] __x64_sys_write+0x97/0xf0 [ 70.208810][ T9350] x64_sys_call+0x3015/0x3cf0 [ 70.209255][ T9350] do_syscall_64+0xd9/0x1d0 [ 70.209680][ T9350] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 70.210230][ T9350] [ 70.210454][ T9350] CPU: 2 UID: 0 PID: 9350 Comm: repro Not tainted 6.12.0-rc5 #5 [ 70.211174][ T9350] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 70.212115][ T9350] ===================================================== [ 70.212734][ T9350] Disabling lock debugging due to kernel taint [ 70.213284][ T9350] Kernel panic - not syncing: kmsan.panic set ... [ 70.213858][ T9350] CPU: 2 UID: 0 PID: 9350 Comm: repro Tainted: G B 6.12.0-rc5 #5 [ 70.214679][ T9350] Tainted: [B]=BAD_PAGE [ 70.215057][ T9350] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 70.215999][ T9350] Call Trace: [ 70.216309][ T9350] <TASK> [ 70.216585][ T9350] dump_stack_lvl+0x1fd/0x2b0 [ 70.217025][ T9350] dump_stack+0x1e/0x30 [ 70.217421][ T9350] panic+0x502/0xca0 [ 70.217803][ T9350] ? kmsan_get_metadata+0x13e/0x1c0 [ 70.218294][ Message fromT sy9350] kmsan_report+0x296/slogd@syzkaller 0x2aat Aug 18 22:11:058 ... kernel :[ 70.213284][ T9350] Kernel panic - not syncing: kmsan.panic [ 70.220179][ T9350] ? kmsan_get_metadata+0x13e/0x1c0 set ... [ 70.221254][ T9350] ? __msan_warning+0x96/0x120 [ 70.222066][ T9350] ? __hfsplus_ext_cache_extent+0x7d0/0x990 [ 70.223023][ T9350] ? hfsplus_file_extend+0x74f/0x1cf0 [ 70.224120][ T9350] ? hfsplus_get_block+0xe16/0x17b0 [ 70.224946][ T9350] ? __block_write_begin_int+0x962/0x2ce0 [ 70.225756][ T9350] ? cont_write_begin+0x1000/0x1950 [ 70.226337][ T9350] ? hfsplus_write_begin+0x85/0x130 [ 70.226852][ T9350] ? generic_perform_write+0x3e8/0x1060 [ 70.227405][ T9350] ? __generic_file_write_iter+0x215/0x460 [ 70.227979][ T9350] ? generic_file_write_iter+0x109/0x5e0 [ 70.228540][ T9350] ? vfs_write+0xb0f/0x14e0 [ 70.228997][ T9350] ? ksys_write+0x23e/0x490 ---truncated---
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < c1ec90bed504640a42bb20a5f413be39cd17ad71 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < b8a72692aa42b7dcd179a96b90bc2763ac74576a (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < c135b8dca65526aa5b8814e9954e0ae317d9c598 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < d7e313039a8f3a6ee072dc5ff4643234d2d735cf (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < a5bfb13b4f406aef1a450f99d22d3e48df01528c (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 99202d94909d323a30d154ab0261c0a07166daec (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 14c673a2f3ecf650b694a52a88688f1d71849899 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 4840ceadef4290c56cc422f0fc697655f3cbf070 (git)
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Linux Linux Affected: 2.6.12
Unaffected: 0 , < 2.6.12 (semver)
Unaffected: 5.4.301 , ≤ 5.4.* (semver)
Unaffected: 5.10.246 , ≤ 5.10.* (semver)
Unaffected: 5.15.196 , ≤ 5.15.* (semver)
Unaffected: 6.1.158 , ≤ 6.1.* (semver)
Unaffected: 6.6.115 , ≤ 6.6.* (semver)
Unaffected: 6.12.56 , ≤ 6.12.* (semver)
Unaffected: 6.17.6 , ≤ 6.17.* (semver)
Unaffected: 6.18 , ≤ * (original_commit_for_fix)
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{
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              "status": "unaffected",
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              "versionType": "semver"
            },
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              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.246",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.196",
              "versionType": "semver"
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            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.158",
              "versionType": "semver"
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              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
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              "versionType": "semver"
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhfsplus: fix KMSAN uninit-value issue in __hfsplus_ext_cache_extent()\n\nThe syzbot reported issue in __hfsplus_ext_cache_extent():\n\n[   70.194323][ T9350] BUG: KMSAN: uninit-value in __hfsplus_ext_cache_extent+0x7d0/0x990\n[   70.195022][ T9350]  __hfsplus_ext_cache_extent+0x7d0/0x990\n[   70.195530][ T9350]  hfsplus_file_extend+0x74f/0x1cf0\n[   70.195998][ T9350]  hfsplus_get_block+0xe16/0x17b0\n[   70.196458][ T9350]  __block_write_begin_int+0x962/0x2ce0\n[   70.196959][ T9350]  cont_write_begin+0x1000/0x1950\n[   70.197416][ T9350]  hfsplus_write_begin+0x85/0x130\n[   70.197873][ T9350]  generic_perform_write+0x3e8/0x1060\n[   70.198374][ T9350]  __generic_file_write_iter+0x215/0x460\n[   70.198892][ T9350]  generic_file_write_iter+0x109/0x5e0\n[   70.199393][ T9350]  vfs_write+0xb0f/0x14e0\n[   70.199771][ T9350]  ksys_write+0x23e/0x490\n[   70.200149][ T9350]  __x64_sys_write+0x97/0xf0\n[   70.200570][ T9350]  x64_sys_call+0x3015/0x3cf0\n[   70.201065][ T9350]  do_syscall_64+0xd9/0x1d0\n[   70.201506][ T9350]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\n[   70.202054][ T9350]\n[   70.202279][ T9350] Uninit was created at:\n[   70.202693][ T9350]  __kmalloc_noprof+0x621/0xf80\n[   70.203149][ T9350]  hfsplus_find_init+0x8d/0x1d0\n[   70.203602][ T9350]  hfsplus_file_extend+0x6ca/0x1cf0\n[   70.204087][ T9350]  hfsplus_get_block+0xe16/0x17b0\n[   70.204561][ T9350]  __block_write_begin_int+0x962/0x2ce0\n[   70.205074][ T9350]  cont_write_begin+0x1000/0x1950\n[   70.205547][ T9350]  hfsplus_write_begin+0x85/0x130\n[   70.206017][ T9350]  generic_perform_write+0x3e8/0x1060\n[   70.206519][ T9350]  __generic_file_write_iter+0x215/0x460\n[   70.207042][ T9350]  generic_file_write_iter+0x109/0x5e0\n[   70.207552][ T9350]  vfs_write+0xb0f/0x14e0\n[   70.207961][ T9350]  ksys_write+0x23e/0x490\n[   70.208375][ T9350]  __x64_sys_write+0x97/0xf0\n[   70.208810][ T9350]  x64_sys_call+0x3015/0x3cf0\n[   70.209255][ T9350]  do_syscall_64+0xd9/0x1d0\n[   70.209680][ T9350]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\n[   70.210230][ T9350]\n[   70.210454][ T9350] CPU: 2 UID: 0 PID: 9350 Comm: repro Not tainted 6.12.0-rc5 #5\n[   70.211174][ T9350] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[   70.212115][ T9350] =====================================================\n[   70.212734][ T9350] Disabling lock debugging due to kernel taint\n[   70.213284][ T9350] Kernel panic - not syncing: kmsan.panic set ...\n[   70.213858][ T9350] CPU: 2 UID: 0 PID: 9350 Comm: repro Tainted: G    B              6.12.0-rc5 #5\n[   70.214679][ T9350] Tainted: [B]=BAD_PAGE\n[   70.215057][ T9350] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[   70.215999][ T9350] Call Trace:\n[   70.216309][ T9350]  \u003cTASK\u003e\n[   70.216585][ T9350]  dump_stack_lvl+0x1fd/0x2b0\n[   70.217025][ T9350]  dump_stack+0x1e/0x30\n[   70.217421][ T9350]  panic+0x502/0xca0\n[   70.217803][ T9350]  ? kmsan_get_metadata+0x13e/0x1c0\n\n[   70.218294][ Message fromT sy9350]  kmsan_report+0x296/slogd@syzkaller 0x2aat Aug 18 22:11:058 ...\n kernel\n:[   70.213284][ T9350] Kernel panic - not syncing: kmsan.panic [   70.220179][ T9350]  ? kmsan_get_metadata+0x13e/0x1c0\nset ...\n[   70.221254][ T9350]  ? __msan_warning+0x96/0x120\n[   70.222066][ T9350]  ? __hfsplus_ext_cache_extent+0x7d0/0x990\n[   70.223023][ T9350]  ? hfsplus_file_extend+0x74f/0x1cf0\n[   70.224120][ T9350]  ? hfsplus_get_block+0xe16/0x17b0\n[   70.224946][ T9350]  ? __block_write_begin_int+0x962/0x2ce0\n[   70.225756][ T9350]  ? cont_write_begin+0x1000/0x1950\n[   70.226337][ T9350]  ? hfsplus_write_begin+0x85/0x130\n[   70.226852][ T9350]  ? generic_perform_write+0x3e8/0x1060\n[   70.227405][ T9350]  ? __generic_file_write_iter+0x215/0x460\n[   70.227979][ T9350]  ? generic_file_write_iter+0x109/0x5e0\n[   70.228540][ T9350]  ? vfs_write+0xb0f/0x14e0\n[   70.228997][ T9350]  ? ksys_write+0x23e/0x490\n---truncated---"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The defect is only reachable by mounting an attacker-authored HFS+ block device or image locally and then issuing ordinary file syscalls (read/write/unlink) against it; there is no network, adjacent-network, or remote-peer data path into hfsplus_get_block() or hfs_brec_find(). Local mounting of attacker-supplied images is routinely available via udisks2/automount, loop devices, and fstab `user` entries.\nAC:L - Every precondition comes from attacker-authored on-disk metadata: setting vhdr-\u003enext_cnid to 0 deterministically yields inode-\u003ei_ino == 0 so the cnid comparison matches, and an extents b-tree header with root == 0 (or an index node with a zero record offset) deterministically forces the uninitialized-field return path; the residual uninitialized slab/stack values are groomable from userspace with standard techniques and the syzbot reproducer triggers the bug reliably with no race or uncontrollable condition.\nPR:L - hfsplus is registered FS_REQUIRES_DEV without FS_USERNS_MOUNT, so the mount itself needs CAP_SYS_ADMIN in the initial namespace and is not obtainable via unshare -Ur; however, once a privileged automounter such as udisks2 has mounted the removable volume, an ordinary unprivileged local user drives the entire hfsplus_get_block \u2192 hfsplus_file_extend \u2192 __hfsplus_ext_read_extent path with a plain write(), with no capability check anywhere along it.\nUI:N - In the removable-media/udisks2 automount scenario the crafted volume is mounted without any deliberate victim action, and the trigger itself is a normal file read or write performed by the attacker on their own image.\nS:U - The uninitialized-memory consumption, the resulting out-of-bounds page accesses, and any fault all occur inside the host kernel\u0027s own security authority; no VM, hypervisor, IOMMU, or sandbox boundary is crossed.\nC:H - The uninitialized fd-\u003erecord and fd-\u003eentryoffset gate and then feed hfs_bnode_read(bnode, \u0026data, off, 4) in the hfs_brec_find() index-node loop, where the unvalidated offset indexes node-\u003epage[] out of bounds and dereferences arbitrary slab contents as a struct page *, giving an unbounded kernel-memory read; in addition, stale kmalloc\u0027d bytes from fd-\u003ekey seed hip-\u003ecached_start/cached_extents, which are persisted into on-disk metadata the attacker reads back.\nI:H - On the hfsplus_free_fork() path, __hfsplus_ext_read_extent() can return success with uninitialized fields, after which hfs_brec_remove() performs hfs_bnode_write_u16() and hfs_bnode_move() using the garbage fd-\u003erecord, fd-\u003ekeyoffset and fd-\u003ekeylength+fd-\u003eentrylength, producing out-of-bounds writes into kernel page data; garbage extent records additionally steer map_bh() to arbitrary device sectors.\nA:H - On the tree-\u003eroot == 0 path fd-\u003ebnode is NULL, so once the uninitialized entrylength passes the \"!= sizeof(hfsplus_extent_rec)\" check the code dereferences a NULL bnode in hfs_bnode_read(); the reported syzbot outcome is already \"Kernel panic - not syncing\", and a persistent crafted volume retriggers the fault on every access."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:08:48.412Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/c1ec90bed504640a42bb20a5f413be39cd17ad71"
        },
        {
          "url": "https://git.kernel.org/stable/c/b8a72692aa42b7dcd179a96b90bc2763ac74576a"
        },
        {
          "url": "https://git.kernel.org/stable/c/c135b8dca65526aa5b8814e9954e0ae317d9c598"
        },
        {
          "url": "https://git.kernel.org/stable/c/d7e313039a8f3a6ee072dc5ff4643234d2d735cf"
        },
        {
          "url": "https://git.kernel.org/stable/c/a5bfb13b4f406aef1a450f99d22d3e48df01528c"
        },
        {
          "url": "https://git.kernel.org/stable/c/99202d94909d323a30d154ab0261c0a07166daec"
        },
        {
          "url": "https://git.kernel.org/stable/c/14c673a2f3ecf650b694a52a88688f1d71849899"
        },
        {
          "url": "https://git.kernel.org/stable/c/4840ceadef4290c56cc422f0fc697655f3cbf070"
        }
      ],
      "title": "hfsplus: fix KMSAN uninit-value issue in __hfsplus_ext_cache_extent()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-40244",
    "datePublished": "2025-12-04T15:31:33.249Z",
    "dateReserved": "2025-04-16T07:20:57.181Z",
    "dateUpdated": "2026-08-05T12:08:48.412Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-40244",
      "date": "2026-09-16",
      "epss": "0.00155",
      "percentile": "0.04998"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-40244\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-12-04T16:16:17.670\",\"lastModified\":\"2026-07-30T06:24:20.907\",\"vulnStatus\":\"Deferred\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nhfsplus: fix KMSAN uninit-value issue in __hfsplus_ext_cache_extent()\\n\\nThe syzbot reported issue in __hfsplus_ext_cache_extent():\\n\\n[   70.194323][ T9350] BUG: KMSAN: uninit-value in __hfsplus_ext_cache_extent+0x7d0/0x990\\n[   70.195022][ T9350]  __hfsplus_ext_cache_extent+0x7d0/0x990\\n[   70.195530][ T9350]  hfsplus_file_extend+0x74f/0x1cf0\\n[   70.195998][ T9350]  hfsplus_get_block+0xe16/0x17b0\\n[   70.196458][ T9350]  __block_write_begin_int+0x962/0x2ce0\\n[   70.196959][ T9350]  cont_write_begin+0x1000/0x1950\\n[   70.197416][ T9350]  hfsplus_write_begin+0x85/0x130\\n[   70.197873][ T9350]  generic_perform_write+0x3e8/0x1060\\n[   70.198374][ T9350]  __generic_file_write_iter+0x215/0x460\\n[   70.198892][ T9350]  generic_file_write_iter+0x109/0x5e0\\n[   70.199393][ T9350]  vfs_write+0xb0f/0x14e0\\n[   70.199771][ T9350]  ksys_write+0x23e/0x490\\n[   70.200149][ T9350]  __x64_sys_write+0x97/0xf0\\n[   70.200570][ T9350]  x64_sys_call+0x3015/0x3cf0\\n[   70.201065][ T9350]  do_syscall_64+0xd9/0x1d0\\n[   70.201506][ T9350]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\\n[   70.202054][ T9350]\\n[   70.202279][ T9350] Uninit was created at:\\n[   70.202693][ T9350]  __kmalloc_noprof+0x621/0xf80\\n[   70.203149][ T9350]  hfsplus_find_init+0x8d/0x1d0\\n[   70.203602][ T9350]  hfsplus_file_extend+0x6ca/0x1cf0\\n[   70.204087][ T9350]  hfsplus_get_block+0xe16/0x17b0\\n[   70.204561][ T9350]  __block_write_begin_int+0x962/0x2ce0\\n[   70.205074][ T9350]  cont_write_begin+0x1000/0x1950\\n[   70.205547][ T9350]  hfsplus_write_begin+0x85/0x130\\n[   70.206017][ T9350]  generic_perform_write+0x3e8/0x1060\\n[   70.206519][ T9350]  __generic_file_write_iter+0x215/0x460\\n[   70.207042][ T9350]  generic_file_write_iter+0x109/0x5e0\\n[   70.207552][ T9350]  vfs_write+0xb0f/0x14e0\\n[   70.207961][ T9350]  ksys_write+0x23e/0x490\\n[   70.208375][ T9350]  __x64_sys_write+0x97/0xf0\\n[   70.208810][ T9350]  x64_sys_call+0x3015/0x3cf0\\n[   70.209255][ T9350]  do_syscall_64+0xd9/0x1d0\\n[   70.209680][ T9350]  entry_SYSCALL_64_after_hwframe+0x77/0x7f\\n[   70.210230][ T9350]\\n[   70.210454][ T9350] CPU: 2 UID: 0 PID: 9350 Comm: repro Not tainted 6.12.0-rc5 #5\\n[   70.211174][ T9350] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\\n[   70.212115][ T9350] =====================================================\\n[   70.212734][ T9350] Disabling lock debugging due to kernel taint\\n[   70.213284][ T9350] Kernel panic - not syncing: kmsan.panic set ...\\n[   70.213858][ T9350] CPU: 2 UID: 0 PID: 9350 Comm: repro Tainted: G    B              6.12.0-rc5 #5\\n[   70.214679][ T9350] Tainted: [B]=BAD_PAGE\\n[   70.215057][ T9350] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\\n[   70.215999][ T9350] Call Trace:\\n[   70.216309][ T9350]  \u003cTASK\u003e\\n[   70.216585][ T9350]  dump_stack_lvl+0x1fd/0x2b0\\n[   70.217025][ T9350]  dump_stack+0x1e/0x30\\n[   70.217421][ T9350]  panic+0x502/0xca0\\n[   70.217803][ T9350]  ? kmsan_get_metadata+0x13e/0x1c0\\n\\n[   70.218294][ Message fromT sy9350]  kmsan_report+0x296/slogd@syzkaller 0x2aat Aug 18 22:11:058 ...\\n kernel\\n:[   70.213284][ T9350] Kernel panic - not syncing: kmsan.panic [   70.220179][ T9350]  ? kmsan_get_metadata+0x13e/0x1c0\\nset ...\\n[   70.221254][ T9350]  ? __msan_warning+0x96/0x120\\n[   70.222066][ T9350]  ? __hfsplus_ext_cache_extent+0x7d0/0x990\\n[   70.223023][ T9350]  ? hfsplus_file_extend+0x74f/0x1cf0\\n[   70.224120][ T9350]  ? hfsplus_get_block+0xe16/0x17b0\\n[   70.224946][ T9350]  ? __block_write_begin_int+0x962/0x2ce0\\n[   70.225756][ T9350]  ? cont_write_begin+0x1000/0x1950\\n[   70.226337][ T9350]  ? hfsplus_write_begin+0x85/0x130\\n[   70.226852][ T9350]  ? generic_perform_write+0x3e8/0x1060\\n[   70.227405][ T9350]  ? __generic_file_write_iter+0x215/0x460\\n[   70.227979][ T9350]  ? generic_file_write_iter+0x109/0x5e0\\n[   70.228540][ T9350]  ? vfs_write+0xb0f/0x14e0\\n[   70.228997][ T9350]  ? ksys_write+0x23e/0x490\\n---truncated---\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/hfsplus/bfind.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\"lessThan\":\"c1ec90bed504640a42bb20a5f413be39cd17ad71\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\"lessThan\":\"b8a72692aa42b7dcd179a96b90bc2763ac74576a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\"lessThan\":\"c135b8dca65526aa5b8814e9954e0ae317d9c598\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\"lessThan\":\"d7e313039a8f3a6ee072dc5ff4643234d2d735cf\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\"lessThan\":\"a5bfb13b4f406aef1a450f99d22d3e48df01528c\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\"lessThan\":\"99202d94909d323a30d154ab0261c0a07166daec\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\"lessThan\":\"14c673a2f3ecf650b694a52a88688f1d71849899\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\",\"lessThan\":\"4840ceadef4290c56cc422f0fc697655f3cbf070\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/hfsplus/bfind.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\":\"5.15.196\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.158\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.115\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.56\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.17.6\",\"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:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/14c673a2f3ecf650b694a52a88688f1d71849899\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/4840ceadef4290c56cc422f0fc697655f3cbf070\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/99202d94909d323a30d154ab0261c0a07166daec\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/a5bfb13b4f406aef1a450f99d22d3e48df01528c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b8a72692aa42b7dcd179a96b90bc2763ac74576a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c135b8dca65526aa5b8814e9954e0ae317d9c598\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c1ec90bed504640a42bb20a5f413be39cd17ad71\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/d7e313039a8f3a6ee072dc5ff4643234d2d735cf\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-30T08:38:08+00:00",
      "cve": "CVE-2025-40244",
      "id": "CVE-2025-40244",
      "initial_release_date": "2025-12-04T00:00:00+00:00",
      "product_status:known_affected": "14",
      "product_status:known_not_affected": "260",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: hfsplus: fix KMSAN uninit-value issue in __hfsplus_ext_cache_extent()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-40244.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-29T01:15:08Z",
      "cve": "CVE-2025-40244",
      "id": "CVE-2025-40244",
      "initial_release_date": "2025-12-05T00:25:38Z",
      "product_status:known_affected": "394",
      "product_status:known_not_affected": "392",
      "product_status:recommended": "249",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-40244",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-40244.json",
      "version": "34"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.