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7.8
HIGH CVSS 3.1
CVE-2026-64300
perf/aux: Fix page UAF in map_range()
Overview
Description

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().

Details
INFO

Published Date :

July 25, 2026, 10:17 a.m.

Last Modified :

Aug. 17, 2026, 5:17 a.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Impact
Affected Products

The following products are affected by CVE-2026-64300 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
Resolve Use-After-Free in map_range by acquiring aux_mutex during page walk.
  • Acquire rb->aux_mutex before walking pages in map_range.
  • Ensure proper synchronization between events sharing an rb.
  • Apply the provided kernel patch for perf/aux.
  • Update the Linux kernel to the latest stable version.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-64300.

URL Resource
https://git.kernel.org/stable/c/0cff05bd2186020f8706233e261016d149cc24db
https://git.kernel.org/stable/c/5948aaf64f81f217a25dcc2bf6c0779bca19566c
https://git.kernel.org/stable/c/c8b7e113f7b61eef2f017e6329c27c2331058c5a
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-64300 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-64300 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-64300 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-64300 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Aug. 17, 2026

    Action Type Old Value New Value
    Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'b709eb872e19a19607bbb6d2975bc264d59735cf', 'lessThan': 'c8b7e113f7b61eef2f017e6329c27c2331058c5a', 'versionType': 'git'}, {'status': 'affected', 'version': 'b709eb872e19a19607bbb6d2975bc264d59735cf', 'lessThan': '0cff05bd2186020f8706233e261016d149cc24db', 'versionType': 'git'}, {'status': 'affected', 'version': 'b709eb872e19a19607bbb6d2975bc264d59735cf', 'lessThan': '5948aaf64f81f217a25dcc2bf6c0779bca19566c', 'versionType': 'git'}], 'programFiles': ['kernel/events/core.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.14'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.14', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc3', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/events/core.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'b709eb872e19a19607bbb6d2975bc264d59735cf', 'lessThan': 'c8b7e113f7b61eef2f017e6329c27c2331058c5a', 'versionType': 'git'}, {'status': 'affected', 'version': 'b709eb872e19a19607bbb6d2975bc264d59735cf', 'lessThan': '0cff05bd2186020f8706233e261016d149cc24db', 'versionType': 'git'}, {'status': 'affected', 'version': 'b709eb872e19a19607bbb6d2975bc264d59735cf', 'lessThan': '5948aaf64f81f217a25dcc2bf6c0779bca19566c', 'versionType': 'git'}], 'programFiles': ['kernel/events/core.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.14'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.14', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/events/core.c'], 'defaultStatus': 'affected'}]
  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jul. 27, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jul. 25, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'b709eb872e19a19607bbb6d2975bc264d59735cf', 'lessThan': 'c8b7e113f7b61eef2f017e6329c27c2331058c5a', 'versionType': 'git'}, {'status': 'affected', 'version': 'b709eb872e19a19607bbb6d2975bc264d59735cf', 'lessThan': '0cff05bd2186020f8706233e261016d149cc24db', 'versionType': 'git'}, {'status': 'affected', 'version': 'b709eb872e19a19607bbb6d2975bc264d59735cf', 'lessThan': '5948aaf64f81f217a25dcc2bf6c0779bca19566c', 'versionType': 'git'}], 'programFiles': ['kernel/events/core.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.14'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.14', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc3', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/events/core.c'], 'defaultStatus': 'affected'}]
    Added Description 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().
    Added Reference https://git.kernel.org/stable/c/0cff05bd2186020f8706233e261016d149cc24db
    Added Reference https://git.kernel.org/stable/c/5948aaf64f81f217a25dcc2bf6c0779bca19566c
    Added Reference https://git.kernel.org/stable/c/c8b7e113f7b61eef2f017e6329c27c2331058c5a
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 7.8
Attack Vector
Attack Complexity
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