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
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6653 records in the last 180 days details
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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}



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