CVE-2026-64300 (GCVE-0-2026-64300)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:49 – Updated: 2026-08-17 04:52
VLAI
Title
perf/aux: Fix page UAF in map_range()
Summary
In the Linux kernel, the following vulnerability has been resolved: perf/aux: Fix page UAF in map_range() map_range() reads rb->aux_pages[], rb->aux_nr_pages and rb->aux_pgoff via perf_mmap_to_page() while holding only event->mmap_mutex. Those fields are serialized by rb->aux_mutex, and mmap_mutex is per event. Thus, two events sharing one rb via PERF_EVENT_IOC_SET_OUTPUT can race rb_alloc_aux() with map_range(), leading to a page-UAF scenario as follows: CPU 0 CPU 1 ===== ===== rb_alloc_aux() map_range() [1]: allocate rb->aux_pages[0] [2]: rb->aux_nr_pages++ [3]: perf_mmap_to_page() returns rb->aux_pages[0] [4]: map it as VM_PFNMAP [5]: rb->aux_pgoff = 1 munmap the page [6]: free rb->aux_pages[0] Pages mapped as VM_PFNMAP have no refcount protection, so CPU 1 holds a mapping to a freed physical frame. Fix this by taking rb->aux_mutex across the page walk in map_range().
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: b709eb872e19a19607bbb6d2975bc264d59735cf , < c8b7e113f7b61eef2f017e6329c27c2331058c5a (git)
Affected: b709eb872e19a19607bbb6d2975bc264d59735cf , < 0cff05bd2186020f8706233e261016d149cc24db (git)
Affected: b709eb872e19a19607bbb6d2975bc264d59735cf , < 5948aaf64f81f217a25dcc2bf6c0779bca19566c (git)
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Linux Linux Affected: 6.14
Unaffected: 0 , < 6.14 (semver)
Unaffected: 6.18.39 , ≤ 6.18.* (semver)
Unaffected: 7.1.4 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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      "current_release_date": "2026-09-10T21:04:07+00:00",
      "cve": "CVE-2026-64300",
      "id": "CVE-2026-64300",
      "initial_release_date": "2026-07-25T00:00:00+00:00",
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      "current_release_date": "2026-09-15T01:52:25Z",
      "cve": "CVE-2026-64300",
      "id": "CVE-2026-64300",
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      "product_status:known_affected": "29",
      "product_status:known_not_affected": "347",
      "product_status:recommended": "46",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64300",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64300.json",
      "version": "7"
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}



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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • 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.


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