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CVE-2022-50630 (GCVE-0-2022-50630)

Vulnerability from cvelistv5 – Published: 2025-12-08 01:16 – Updated: 2026-08-05 08:59
VLAI
Title
mm: hugetlb: fix UAF in hugetlb_handle_userfault
Summary
In the Linux kernel, the following vulnerability has been resolved: mm: hugetlb: fix UAF in hugetlb_handle_userfault The vma_lock and hugetlb_fault_mutex are dropped before handling userfault and reacquire them again after handle_userfault(), but reacquire the vma_lock could lead to UAF[1,2] due to the following race, hugetlb_fault hugetlb_no_page /*unlock vma_lock */ hugetlb_handle_userfault handle_userfault /* unlock mm->mmap_lock*/ vm_mmap_pgoff do_mmap mmap_region munmap_vma_range /* clean old vma */ /* lock vma_lock again <--- UAF */ /* unlock vma_lock */ Since the vma_lock will unlock immediately after hugetlb_handle_userfault(), let's drop the unneeded lock and unlock in hugetlb_handle_userfault() to fix the issue. [1] https://lore.kernel.org/linux-mm/000000000000d5e00a05e834962e@google.com/ [2] https://lore.kernel.org/linux-mm/20220921014457.1668-1-liuzixian4@huawei.com/
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: 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 , < 45c33966759ea1b4040c08dacda99ef623c0ca29 (git)
Affected: 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 , < 0db2efb3bff879566f05341d94c3de00ac95c4cc (git)
Affected: 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 , < dd691973f67b2800a97db723b1ff6f07fdcf7f5a (git)
Affected: 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 , < 78504bcedb2f1bbfb353b4d233c24d641c4dda33 (git)
Affected: 1a1aad8a9b7bd34f60cdf98cd7915f00ae892c45 , < 958f32ce832ba781ac20e11bb2d12a9352ea28fc (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.11
Unaffected: 0 , < 4.11 (semver)
Unaffected: 5.10.150 , ≤ 5.10.* (semver)
Unaffected: 5.15.75 , ≤ 5.15.* (semver)
Unaffected: 5.19.17 , ≤ 5.19.* (semver)
Unaffected: 6.0.3 , ≤ 6.0.* (semver)
Unaffected: 6.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: hugetlb: fix UAF in hugetlb_handle_userfault\n\nThe vma_lock and hugetlb_fault_mutex are dropped before handling userfault\nand reacquire them again after handle_userfault(), but reacquire the\nvma_lock could lead to UAF[1,2] due to the following race,\n\nhugetlb_fault\n  hugetlb_no_page\n    /*unlock vma_lock */\n    hugetlb_handle_userfault\n      handle_userfault\n        /* unlock mm-\u003emmap_lock*/\n                                           vm_mmap_pgoff\n                                             do_mmap\n                                               mmap_region\n                                                 munmap_vma_range\n                                                   /* clean old vma */\n        /* lock vma_lock again  \u003c--- UAF */\n    /* unlock vma_lock */\n\nSince the vma_lock will unlock immediately after\nhugetlb_handle_userfault(), let\u0027s drop the unneeded lock and unlock in\nhugetlb_handle_userfault() to fix the issue.\n\n[1] https://lore.kernel.org/linux-mm/000000000000d5e00a05e834962e@google.com/\n[2] https://lore.kernel.org/linux-mm/20220921014457.1668-1-liuzixian4@huawei.com/"
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    "datePublished": "2025-12-08T01:16:45.555Z",
    "dateReserved": "2025-12-08T01:14:55.192Z",
    "dateUpdated": "2026-08-05T08:59:13.840Z",
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-04T19:37:22+00:00",
      "cve": "CVE-2022-50630",
      "id": "CVE-2022-50630",
      "initial_release_date": "2022-01-01T00:00:00+00:00",
      "product_status:known_affected": "149",
      "product_status:known_not_affected": "125",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: mm: hugetlb: fix UAF in hugetlb_handle_userfault",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2022/cve-2022-50630.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-02T01:59:55Z",
      "cve": "CVE-2022-50630",
      "id": "CVE-2022-50630",
      "initial_release_date": "2025-12-09T00:31:18Z",
      "product_status:known_affected": "354",
      "product_status:known_not_affected": "362",
      "product_status:recommended": "252",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2022-50630",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2022-50630.json",
      "version": "39"
    }
  }
}



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Sightings

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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.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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