CVE-2026-45251 (GCVE-0-2026-45251)
Vulnerability from cvelistv5
Published
2026-05-21 09:04
Modified
2026-05-22 03:55
CWE
Summary
A file descriptor can be closed while a thread is blocked in a poll(2) or select(2) call waiting for that descriptor. Because the blocked thread does not hold a reference to the underlying object, this closure may result in the object being freed while the thread remains blocked. In this situation, the kernel must remove the blocked thread from the per-object wait queue prior to freeing the object. In the case of some file descriptor types, the kernel failed to unlink blocked threads from the object before freeing it. When the blocked thread is subsequently woken, it accesses memory that has already been freed resulting in a use-after-free vulnerability. The use-after-free vulnerability may be triggered by an unprivileged local user and can be exploited to obtain superuser privileges.
Impacted products
Vendor Product Version
FreeBSD FreeBSD Version: 15.0-RELEASE
Version: 14.4-RELEASE
Version: 14.3-RELEASE
Create a notification for this product.
Show details on NVD website


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              "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",
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          "descriptions": [
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              "description": "CWE-416: Use After Free",
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        "orgId": "63664ac6-956c-4cba-a5d0-f46076e16109",
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    "datePublished": "2026-05-21T09:04:52.569Z",
    "dateReserved": "2026-05-11T16:27:44.891Z",
    "dateUpdated": "2026-05-22T03:55:35.943Z",
    "state": "PUBLISHED"
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  "dataVersion": "5.2"
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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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