FKIE_CVE-2026-22995

Vulnerability from fkie_nvd - Published: 2026-01-23 16:15 - Updated: 2026-02-26 17:13
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: ublk: fix use-after-free in ublk_partition_scan_work A race condition exists between the async partition scan work and device teardown that can lead to a use-after-free of ub->ub_disk: 1. ublk_ctrl_start_dev() schedules partition_scan_work after add_disk() 2. ublk_stop_dev() calls ublk_stop_dev_unlocked() which does: - del_gendisk(ub->ub_disk) - ublk_detach_disk() sets ub->ub_disk = NULL - put_disk() which may free the disk 3. The worker ublk_partition_scan_work() then dereferences ub->ub_disk leading to UAF Fix this by using ublk_get_disk()/ublk_put_disk() in the worker to hold a reference to the disk during the partition scan. The spinlock in ublk_get_disk() synchronizes with ublk_detach_disk() ensuring the worker either gets a valid reference or sees NULL and exits early. Also change flush_work() to cancel_work_sync() to avoid running the partition scan work unnecessarily when the disk is already detached.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/72e28774e9644c2bdbb4920842fbf77103a15a85Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f0d385f6689f37a2828c686fb279121df006b4cbPatch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel 6.19
To clipboard 

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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nublk: fix use-after-free in ublk_partition_scan_work\n\nA race condition exists between the async partition scan work and device\nteardown that can lead to a use-after-free of ub-\u003eub_disk:\n\n1. ublk_ctrl_start_dev() schedules partition_scan_work after add_disk()\n2. ublk_stop_dev() calls ublk_stop_dev_unlocked() which does:\n   - del_gendisk(ub-\u003eub_disk)\n   - ublk_detach_disk() sets ub-\u003eub_disk = NULL\n   - put_disk() which may free the disk\n3. The worker ublk_partition_scan_work() then dereferences ub-\u003eub_disk\n   leading to UAF\n\nFix this by using ublk_get_disk()/ublk_put_disk() in the worker to hold\na reference to the disk during the partition scan. The spinlock in\nublk_get_disk() synchronizes with ublk_detach_disk() ensuring the worker\neither gets a valid reference or sees NULL and exits early.\n\nAlso change flush_work() to cancel_work_sync() to avoid running the\npartition scan work unnecessarily when the disk is already detached."
    }
  ],
  "id": "CVE-2026-22995",
  "lastModified": "2026-02-26T17:13:33.407",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
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        "impactScore": 5.9,
        "source": "nvd@nist.gov",
        "type": "Primary"
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  "published": "2026-01-23T16:15:55.603",
  "references": [
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      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "tags": [
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  "vulnStatus": "Analyzed",
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          "value": "CWE-416"
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      "source": "nvd@nist.gov",
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