CVE-2024-56693 (GCVE-0-2024-56693)

Vulnerability from cvelistv5 – Published: 2024-12-28 09:46 – Updated: 2026-05-11 20:57
VLAI?
Title
brd: defer automatic disk creation until module initialization succeeds
Summary
In the Linux kernel, the following vulnerability has been resolved: brd: defer automatic disk creation until module initialization succeeds My colleague Wupeng found the following problems during fault injection: BUG: unable to handle page fault for address: fffffbfff809d073 PGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 5 UID: 0 PID: 755 Comm: modprobe Not tainted 6.12.0-rc3+ #17 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:__asan_load8+0x4c/0xa0 ... Call Trace: <TASK> blkdev_put_whole+0x41/0x70 bdev_release+0x1a3/0x250 blkdev_release+0x11/0x20 __fput+0x1d7/0x4a0 task_work_run+0xfc/0x180 syscall_exit_to_user_mode+0x1de/0x1f0 do_syscall_64+0x6b/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e loop_init() is calling loop_add() after __register_blkdev() succeeds and is ignoring disk_add() failure from loop_add(), for loop_add() failure is not fatal and successfully created disks are already visible to bdev_open(). brd_init() is currently calling brd_alloc() before __register_blkdev() succeeds and is releasing successfully created disks when brd_init() returns an error. This can cause UAF for the latter two case: case 1: T1: modprobe brd brd_init brd_alloc(0) // success add_disk disk_scan_partitions bdev_file_open_by_dev // alloc file fput // won't free until back to userspace brd_alloc(1) // failed since mem alloc error inject // error path for modprobe will release code segment // back to userspace __fput blkdev_release bdev_release blkdev_put_whole bdev->bd_disk->fops->release // fops is freed now, UAF! case 2: T1: T2: modprobe brd brd_init brd_alloc(0) // success open(/dev/ram0) brd_alloc(1) // fail // error path for modprobe close(/dev/ram0) ... /* UAF! */ bdev->bd_disk->fops->release Fix this problem by following what loop_init() does. Besides, reintroduce brd_devices_mutex to help serialize modifications to brd_list.
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 7f9b348cb5e94259acdcbafbcaed55d3bb515304 , < 41219c147df8bbd6591f59af5d695fb6c9a1cbff (git)
Affected: 7f9b348cb5e94259acdcbafbcaed55d3bb515304 , < 259bf925583ec9e3781df778cadf00594095090d (git)
Affected: 7f9b348cb5e94259acdcbafbcaed55d3bb515304 , < 410896624db639500f24f46478b4bfa05c76bf56 (git)
Affected: 7f9b348cb5e94259acdcbafbcaed55d3bb515304 , < c0c2744cd2939ec5999c51dbaf2af16886548b7b (git)
Affected: 7f9b348cb5e94259acdcbafbcaed55d3bb515304 , < 63dfd728b30f79495dacc886127695a379805152 (git)
Affected: 7f9b348cb5e94259acdcbafbcaed55d3bb515304 , < 826cc42adf44930a633d11a5993676d85ddb0842 (git)
Create a notification for this product.
Linux Linux Affected: 5.14
Unaffected: 0 , < 5.14 (semver)
Unaffected: 5.15.174 , ≤ 5.15.* (semver)
Unaffected: 6.1.120 , ≤ 6.1.* (semver)
Unaffected: 6.6.64 , ≤ 6.6.* (semver)
Unaffected: 6.11.11 , ≤ 6.11.* (semver)
Unaffected: 6.12.2 , ≤ 6.12.* (semver)
Unaffected: 6.13 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbrd: defer automatic disk creation until module initialization succeeds\n\nMy colleague Wupeng found the following problems during fault injection:\n\nBUG: unable to handle page fault for address: fffffbfff809d073\nPGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0\nOops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI\nCPU: 5 UID: 0 PID: 755 Comm: modprobe Not tainted 6.12.0-rc3+ #17\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS\n1.16.1-2.fc37 04/01/2014\nRIP: 0010:__asan_load8+0x4c/0xa0\n...\nCall Trace:\n \u003cTASK\u003e\n blkdev_put_whole+0x41/0x70\n bdev_release+0x1a3/0x250\n blkdev_release+0x11/0x20\n __fput+0x1d7/0x4a0\n task_work_run+0xfc/0x180\n syscall_exit_to_user_mode+0x1de/0x1f0\n do_syscall_64+0x6b/0x170\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nloop_init() is calling loop_add() after __register_blkdev() succeeds and\nis ignoring disk_add() failure from loop_add(), for loop_add() failure\nis not fatal and successfully created disks are already visible to\nbdev_open().\n\nbrd_init() is currently calling brd_alloc() before __register_blkdev()\nsucceeds and is releasing successfully created disks when brd_init()\nreturns an error. This can cause UAF for the latter two case:\n\ncase 1:\n    T1:\nmodprobe brd\n  brd_init\n    brd_alloc(0) // success\n      add_disk\n        disk_scan_partitions\n          bdev_file_open_by_dev // alloc file\n          fput // won\u0027t free until back to userspace\n    brd_alloc(1) // failed since mem alloc error inject\n  // error path for modprobe will release code segment\n  // back to userspace\n  __fput\n    blkdev_release\n      bdev_release\n        blkdev_put_whole\n          bdev-\u003ebd_disk-\u003efops-\u003erelease // fops is freed now, UAF!\n\ncase 2:\n    T1:                            T2:\nmodprobe brd\n  brd_init\n    brd_alloc(0) // success\n                                   open(/dev/ram0)\n    brd_alloc(1) // fail\n  // error path for modprobe\n\n                                   close(/dev/ram0)\n                                   ...\n                                   /* UAF! */\n                                   bdev-\u003ebd_disk-\u003efops-\u003erelease\n\nFix this problem by following what loop_init() does. Besides,\nreintroduce brd_devices_mutex to help serialize modifications to\nbrd_list."
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          "url": "https://git.kernel.org/stable/c/826cc42adf44930a633d11a5993676d85ddb0842"
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    "cveId": "CVE-2024-56693",
    "datePublished": "2024-12-28T09:46:18.203Z",
    "dateReserved": "2024-12-27T15:00:39.849Z",
    "dateUpdated": "2026-05-11T20:57:25.374Z",
    "state": "PUBLISHED"
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      "date": "2026-05-20",
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      "descriptions": "[{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nbrd: defer automatic disk creation until module initialization succeeds\\n\\nMy colleague Wupeng found the following problems during fault injection:\\n\\nBUG: unable to handle page fault for address: fffffbfff809d073\\nPGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0\\nOops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI\\nCPU: 5 UID: 0 PID: 755 Comm: modprobe Not tainted 6.12.0-rc3+ #17\\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS\\n1.16.1-2.fc37 04/01/2014\\nRIP: 0010:__asan_load8+0x4c/0xa0\\n...\\nCall Trace:\\n \u003cTASK\u003e\\n blkdev_put_whole+0x41/0x70\\n bdev_release+0x1a3/0x250\\n blkdev_release+0x11/0x20\\n __fput+0x1d7/0x4a0\\n task_work_run+0xfc/0x180\\n syscall_exit_to_user_mode+0x1de/0x1f0\\n do_syscall_64+0x6b/0x170\\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\\n\\nloop_init() is calling loop_add() after __register_blkdev() succeeds and\\nis ignoring disk_add() failure from loop_add(), for loop_add() failure\\nis not fatal and successfully created disks are already visible to\\nbdev_open().\\n\\nbrd_init() is currently calling brd_alloc() before __register_blkdev()\\nsucceeds and is releasing successfully created disks when brd_init()\\nreturns an error. This can cause UAF for the latter two case:\\n\\ncase 1:\\n    T1:\\nmodprobe brd\\n  brd_init\\n    brd_alloc(0) // success\\n      add_disk\\n        disk_scan_partitions\\n          bdev_file_open_by_dev // alloc file\\n          fput // won\u0027t free until back to userspace\\n    brd_alloc(1) // failed since mem alloc error inject\\n  // error path for modprobe will release code segment\\n  // back to userspace\\n  __fput\\n    blkdev_release\\n      bdev_release\\n        blkdev_put_whole\\n          bdev-\u003ebd_disk-\u003efops-\u003erelease // fops is freed now, UAF!\\n\\ncase 2:\\n    T1:                            T2:\\nmodprobe brd\\n  brd_init\\n    brd_alloc(0) // success\\n                                   open(/dev/ram0)\\n    brd_alloc(1) // fail\\n  // error path for modprobe\\n\\n                                   close(/dev/ram0)\\n                                   ...\\n                                   /* UAF! */\\n                                   bdev-\u003ebd_disk-\u003efops-\u003erelease\\n\\nFix this problem by following what loop_init() does. Besides,\\nreintroduce brd_devices_mutex to help serialize modifications to\\nbrd_list.\"}, {\"lang\": \"es\", \"value\": \"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: brd: aplazar la creaci\\u00f3n autom\\u00e1tica de discos hasta que la inicializaci\\u00f3n del m\\u00f3dulo tenga \\u00e9xito. Mi colega Wupeng encontr\\u00f3 los siguientes problemas durante la inyecci\\u00f3n de fallas: ERROR: no se puede gestionar la falla de p\\u00e1gina para la direcci\\u00f3n: fffffbfff809d073 PGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 5 UID: 0 PID: 755 Comm: modprobe No contaminado 6.12.0-rc3+ #17 Nombre del hardware: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:__asan_load8+0x4c/0xa0 ... Seguimiento de llamadas:  blkdev_put_whole+0x41/0x70 bdev_release+0x1a3/0x250 blkdev_release+0x11/0x20 __fput+0x1d7/0x4a0 task_work_run+0xfc/0x180 syscall_exit_to_user_mode+0x1de/0x1f0 do_syscall_64+0x6b/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e loop_init() est\\u00e1 llamando a loop_add() despu\\u00e9s de que __register_blkdev() tenga \\u00e9xito e ignora el error de disk_add() de loop_add(), ya que el error de loop_add() no es fatal y los discos creados correctamente ya est\\u00e1n visibles para bdev_open().brd_init() actualmente est\\u00e1 llamando a brd_alloc() antes de que __register_blkdev() tenga \\u00e9xito y est\\u00e1 liberando discos creados exitosamente cuando brd_init() devuelve un error. Esto puede causar UAF para los \\u00faltimos dos casos: caso 1: T1: modprobe brd brd_init brd_alloc(0) // \\u00e9xito add_disk disk_scan_partitions bdev_file_open_by_dev // asignar archivo fput // no se liberar\\u00e1 hasta que regrese al espacio de usuario brd_alloc(1) // fall\\u00f3 debido a un error de asignaci\\u00f3n de memoria inject // error la ruta para modprobe liberar\\u00e1 el segmento de c\\u00f3digo // de regreso al espacio de usuario __fput blkdev_release bdev_release blkdev_put_whole bdev-\u0026gt;bd_disk-\u0026gt;fops-\u0026gt;release // fops est\\u00e1 liberado ahora, \\u00a1UAF! caso 2: T1: T2: modprobe brd brd_init brd_alloc(0) // \\u00e9xito open(/dev/ram0) brd_alloc(1) // error // ruta de error para modprobe close(/dev/ram0) ... /* UAF! */ bdev-\u0026gt;bd_disk-\u0026gt;fops-\u0026gt;release Solucione este problema siguiendo lo que hace loop_init(). Adem\\u00e1s, vuelva a introducir brd_devices_mutex para ayudar a serializar las modificaciones a brd_list.\"}]",
      "id": "CVE-2024-56693",
      "lastModified": "2024-12-28T10:15:14.833",
      "published": "2024-12-28T10:15:14.833",
      "references": "[{\"url\": \"https://git.kernel.org/stable/c/259bf925583ec9e3781df778cadf00594095090d\", \"source\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}, {\"url\": \"https://git.kernel.org/stable/c/410896624db639500f24f46478b4bfa05c76bf56\", \"source\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}, {\"url\": \"https://git.kernel.org/stable/c/41219c147df8bbd6591f59af5d695fb6c9a1cbff\", \"source\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}, {\"url\": \"https://git.kernel.org/stable/c/63dfd728b30f79495dacc886127695a379805152\", \"source\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}, {\"url\": \"https://git.kernel.org/stable/c/826cc42adf44930a633d11a5993676d85ddb0842\", \"source\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}, {\"url\": \"https://git.kernel.org/stable/c/c0c2744cd2939ec5999c51dbaf2af16886548b7b\", \"source\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]",
      "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "vulnStatus": "Awaiting Analysis"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2024-56693\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2024-12-28T10:15:14.833\",\"lastModified\":\"2025-11-03T21:18:20.057\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nbrd: defer automatic disk creation until module initialization succeeds\\n\\nMy colleague Wupeng found the following problems during fault injection:\\n\\nBUG: unable to handle page fault for address: fffffbfff809d073\\nPGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0\\nOops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI\\nCPU: 5 UID: 0 PID: 755 Comm: modprobe Not tainted 6.12.0-rc3+ #17\\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS\\n1.16.1-2.fc37 04/01/2014\\nRIP: 0010:__asan_load8+0x4c/0xa0\\n...\\nCall Trace:\\n \u003cTASK\u003e\\n blkdev_put_whole+0x41/0x70\\n bdev_release+0x1a3/0x250\\n blkdev_release+0x11/0x20\\n __fput+0x1d7/0x4a0\\n task_work_run+0xfc/0x180\\n syscall_exit_to_user_mode+0x1de/0x1f0\\n do_syscall_64+0x6b/0x170\\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\\n\\nloop_init() is calling loop_add() after __register_blkdev() succeeds and\\nis ignoring disk_add() failure from loop_add(), for loop_add() failure\\nis not fatal and successfully created disks are already visible to\\nbdev_open().\\n\\nbrd_init() is currently calling brd_alloc() before __register_blkdev()\\nsucceeds and is releasing successfully created disks when brd_init()\\nreturns an error. This can cause UAF for the latter two case:\\n\\ncase 1:\\n    T1:\\nmodprobe brd\\n  brd_init\\n    brd_alloc(0) // success\\n      add_disk\\n        disk_scan_partitions\\n          bdev_file_open_by_dev // alloc file\\n          fput // won\u0027t free until back to userspace\\n    brd_alloc(1) // failed since mem alloc error inject\\n  // error path for modprobe will release code segment\\n  // back to userspace\\n  __fput\\n    blkdev_release\\n      bdev_release\\n        blkdev_put_whole\\n          bdev-\u003ebd_disk-\u003efops-\u003erelease // fops is freed now, UAF!\\n\\ncase 2:\\n    T1:                            T2:\\nmodprobe brd\\n  brd_init\\n    brd_alloc(0) // success\\n                                   open(/dev/ram0)\\n    brd_alloc(1) // fail\\n  // error path for modprobe\\n\\n                                   close(/dev/ram0)\\n                                   ...\\n                                   /* UAF! */\\n                                   bdev-\u003ebd_disk-\u003efops-\u003erelease\\n\\nFix this problem by following what loop_init() does. Besides,\\nreintroduce brd_devices_mutex to help serialize modifications to\\nbrd_list.\"},{\"lang\":\"es\",\"value\":\"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: brd: aplazar la creaci\u00f3n autom\u00e1tica de discos hasta que la inicializaci\u00f3n del m\u00f3dulo tenga \u00e9xito. Mi colega Wupeng encontr\u00f3 los siguientes problemas durante la inyecci\u00f3n de fallas: ERROR: no se puede gestionar la falla de p\u00e1gina para la direcci\u00f3n: fffffbfff809d073 PGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 5 UID: 0 PID: 755 Comm: modprobe No contaminado 6.12.0-rc3+ #17 Nombre del hardware: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:__asan_load8+0x4c/0xa0 ... Seguimiento de llamadas:  blkdev_put_whole+0x41/0x70 bdev_release+0x1a3/0x250 blkdev_release+0x11/0x20 __fput+0x1d7/0x4a0 task_work_run+0xfc/0x180 syscall_exit_to_user_mode+0x1de/0x1f0 do_syscall_64+0x6b/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e loop_init() est\u00e1 llamando a loop_add() despu\u00e9s de que __register_blkdev() tenga \u00e9xito e ignora el error de disk_add() de loop_add(), ya que el error de loop_add() no es fatal y los discos creados correctamente ya est\u00e1n visibles para bdev_open().brd_init() actualmente est\u00e1 llamando a brd_alloc() antes de que __register_blkdev() tenga \u00e9xito y est\u00e1 liberando discos creados exitosamente cuando brd_init() devuelve un error. Esto puede causar UAF para los \u00faltimos dos casos: caso 1: T1: modprobe brd brd_init brd_alloc(0) // \u00e9xito add_disk disk_scan_partitions bdev_file_open_by_dev // asignar archivo fput // no se liberar\u00e1 hasta que regrese al espacio de usuario brd_alloc(1) // fall\u00f3 debido a un error de asignaci\u00f3n de memoria inject // error la ruta para modprobe liberar\u00e1 el segmento de c\u00f3digo // de regreso al espacio de usuario __fput blkdev_release bdev_release blkdev_put_whole bdev-\u0026gt;bd_disk-\u0026gt;fops-\u0026gt;release // fops est\u00e1 liberado ahora, \u00a1UAF! caso 2: T1: T2: modprobe brd brd_init brd_alloc(0) // \u00e9xito open(/dev/ram0) brd_alloc(1) // error // ruta de error para modprobe close(/dev/ram0) ... /* UAF! */ bdev-\u0026gt;bd_disk-\u0026gt;fops-\u0026gt;release Solucione este problema siguiendo lo que hace loop_init(). Adem\u00e1s, vuelva a introducir brd_devices_mutex para ayudar a serializar las modificaciones a brd_list.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"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}]},\"weaknesses\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.14\",\"versionEndExcluding\":\"5.15.174\",\"matchCriteriaId\":\"018DF5B7-C996-453C-A0E3-17831086B30F\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.16\",\"versionEndExcluding\":\"6.1.120\",\"matchCriteriaId\":\"09AC6122-E2A4-40FE-9D33-268A1B2EC265\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.2\",\"versionEndExcluding\":\"6.6.64\",\"matchCriteriaId\":\"CA16DEE3-ABEC-4449-9F4A-7A3DC4FC36C7\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.7\",\"versionEndExcluding\":\"6.11.11\",\"matchCriteriaId\":\"21434379-192D-472F-9B54-D45E3650E893\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.12\",\"versionEndExcluding\":\"6.12.2\",\"matchCriteriaId\":\"D8882B1B-2ABC-4838-AC1D-DBDBB5764776\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/259bf925583ec9e3781df778cadf00594095090d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/410896624db639500f24f46478b4bfa05c76bf56\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/41219c147df8bbd6591f59af5d695fb6c9a1cbff\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/63dfd728b30f79495dacc886127695a379805152\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/826cc42adf44930a633d11a5993676d85ddb0842\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/c0c2744cd2939ec5999c51dbaf2af16886548b7b\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CVE Program Container\", \"references\": [{\"url\": \"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html\"}], \"providerMetadata\": {\"orgId\": \"af854a3a-2127-422b-91ae-364da2661108\", \"shortName\": \"CVE\", \"dateUpdated\": \"2025-11-03T20:52:41.179Z\"}}, {\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.8, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"HIGH\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2024-56693\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-02-10T17:12:21.851341Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-416\", \"description\": \"CWE-416 Use After Free\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-02-10T17:12:23.390Z\"}}], \"cna\": {\"title\": \"brd: defer automatic disk creation until module initialization succeeds\", \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"7f9b348cb5e94259acdcbafbcaed55d3bb515304\", \"lessThan\": \"41219c147df8bbd6591f59af5d695fb6c9a1cbff\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"7f9b348cb5e94259acdcbafbcaed55d3bb515304\", \"lessThan\": \"259bf925583ec9e3781df778cadf00594095090d\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"7f9b348cb5e94259acdcbafbcaed55d3bb515304\", \"lessThan\": \"410896624db639500f24f46478b4bfa05c76bf56\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"7f9b348cb5e94259acdcbafbcaed55d3bb515304\", \"lessThan\": \"c0c2744cd2939ec5999c51dbaf2af16886548b7b\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"7f9b348cb5e94259acdcbafbcaed55d3bb515304\", \"lessThan\": \"63dfd728b30f79495dacc886127695a379805152\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"7f9b348cb5e94259acdcbafbcaed55d3bb515304\", \"lessThan\": \"826cc42adf44930a633d11a5993676d85ddb0842\", \"versionType\": \"git\"}], \"programFiles\": [\"drivers/block/brd.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"5.14\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"5.14\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"5.15.174\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.15.*\"}, {\"status\": \"unaffected\", \"version\": \"6.1.120\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.1.*\"}, {\"status\": \"unaffected\", \"version\": \"6.6.64\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.6.*\"}, {\"status\": \"unaffected\", \"version\": \"6.11.11\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.11.*\"}, {\"status\": \"unaffected\", \"version\": \"6.12.2\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.13\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"drivers/block/brd.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/41219c147df8bbd6591f59af5d695fb6c9a1cbff\"}, {\"url\": \"https://git.kernel.org/stable/c/259bf925583ec9e3781df778cadf00594095090d\"}, {\"url\": \"https://git.kernel.org/stable/c/410896624db639500f24f46478b4bfa05c76bf56\"}, {\"url\": \"https://git.kernel.org/stable/c/c0c2744cd2939ec5999c51dbaf2af16886548b7b\"}, {\"url\": \"https://git.kernel.org/stable/c/63dfd728b30f79495dacc886127695a379805152\"}, {\"url\": \"https://git.kernel.org/stable/c/826cc42adf44930a633d11a5993676d85ddb0842\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nbrd: defer automatic disk creation until module initialization succeeds\\n\\nMy colleague Wupeng found the following problems during fault injection:\\n\\nBUG: unable to handle page fault for address: fffffbfff809d073\\nPGD 6e648067 P4D 123ec8067 PUD 123ec4067 PMD 100e38067 PTE 0\\nOops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI\\nCPU: 5 UID: 0 PID: 755 Comm: modprobe Not tainted 6.12.0-rc3+ #17\\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS\\n1.16.1-2.fc37 04/01/2014\\nRIP: 0010:__asan_load8+0x4c/0xa0\\n...\\nCall Trace:\\n \u003cTASK\u003e\\n blkdev_put_whole+0x41/0x70\\n bdev_release+0x1a3/0x250\\n blkdev_release+0x11/0x20\\n __fput+0x1d7/0x4a0\\n task_work_run+0xfc/0x180\\n syscall_exit_to_user_mode+0x1de/0x1f0\\n do_syscall_64+0x6b/0x170\\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\\n\\nloop_init() is calling loop_add() after __register_blkdev() succeeds and\\nis ignoring disk_add() failure from loop_add(), for loop_add() failure\\nis not fatal and successfully created disks are already visible to\\nbdev_open().\\n\\nbrd_init() is currently calling brd_alloc() before __register_blkdev()\\nsucceeds and is releasing successfully created disks when brd_init()\\nreturns an error. This can cause UAF for the latter two case:\\n\\ncase 1:\\n    T1:\\nmodprobe brd\\n  brd_init\\n    brd_alloc(0) // success\\n      add_disk\\n        disk_scan_partitions\\n          bdev_file_open_by_dev // alloc file\\n          fput // won\u0027t free until back to userspace\\n    brd_alloc(1) // failed since mem alloc error inject\\n  // error path for modprobe will release code segment\\n  // back to userspace\\n  __fput\\n    blkdev_release\\n      bdev_release\\n        blkdev_put_whole\\n          bdev-\u003ebd_disk-\u003efops-\u003erelease // fops is freed now, UAF!\\n\\ncase 2:\\n    T1:                            T2:\\nmodprobe brd\\n  brd_init\\n    brd_alloc(0) // success\\n                                   open(/dev/ram0)\\n    brd_alloc(1) // fail\\n  // error path for modprobe\\n\\n                                   close(/dev/ram0)\\n                                   ...\\n                                   /* UAF! */\\n                                   bdev-\u003ebd_disk-\u003efops-\u003erelease\\n\\nFix this problem by following what loop_init() does. Besides,\\nreintroduce brd_devices_mutex to help serialize modifications to\\nbrd_list.\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.15.174\", \"versionStartIncluding\": \"5.14\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.1.120\", \"versionStartIncluding\": \"5.14\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.6.64\", \"versionStartIncluding\": \"5.14\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.11.11\", \"versionStartIncluding\": \"5.14\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.2\", \"versionStartIncluding\": \"5.14\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.13\", \"versionStartIncluding\": \"5.14\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-05-11T20:57:25.374Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2024-56693\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-05-11T20:57:25.374Z\", \"dateReserved\": \"2024-12-27T15:00:39.849Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2024-12-28T09:46:18.203Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


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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.