CVE-2026-64300 (GCVE-0-2026-64300)
Vulnerability from cvelistv5 – Published: 2026-07-25 08:49 – Updated: 2026-08-17 04:52
VLAI
EPSS
VEX
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)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
b709eb872e19a19607bbb6d2975bc264d59735cf , < c8b7e113f7b61eef2f017e6329c27c2331058c5a
(git)
Affected: b709eb872e19a19607bbb6d2975bc264d59735cf , < 0cff05bd2186020f8706233e261016d149cc24db (git) Affected: b709eb872e19a19607bbb6d2975bc264d59735cf , < 5948aaf64f81f217a25dcc2bf6c0779bca19566c (git) |
guessed | |
| 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) |
guessed |
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"kernel/events/core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "c8b7e113f7b61eef2f017e6329c27c2331058c5a",
"status": "affected",
"version": "b709eb872e19a19607bbb6d2975bc264d59735cf",
"versionType": "git"
},
{
"lessThan": "0cff05bd2186020f8706233e261016d149cc24db",
"status": "affected",
"version": "b709eb872e19a19607bbb6d2975bc264d59735cf",
"versionType": "git"
},
{
"lessThan": "5948aaf64f81f217a25dcc2bf6c0779bca19566c",
"status": "affected",
"version": "b709eb872e19a19607bbb6d2975bc264d59735cf",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"kernel/events/core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.14"
},
{
"lessThan": "6.14",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.39",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.4",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.39",
"versionStartIncluding": "6.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1.4",
"versionStartIncluding": "6.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2",
"versionStartIncluding": "6.14",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf/aux: Fix page UAF in map_range()\n\nmap_range() reads rb-\u003eaux_pages[], rb-\u003eaux_nr_pages and rb-\u003eaux_pgoff via\nperf_mmap_to_page() while holding only event-\u003emmap_mutex. Those fields are\nserialized by rb-\u003eaux_mutex, and mmap_mutex is per event.\n\nThus, two events sharing one rb via PERF_EVENT_IOC_SET_OUTPUT can race\nrb_alloc_aux() with map_range(), leading to a page-UAF scenario as follows:\n\n CPU 0 CPU 1\n ===== =====\n rb_alloc_aux() map_range()\n [1]: allocate rb-\u003eaux_pages[0]\n [2]: rb-\u003eaux_nr_pages++\n [3]: perf_mmap_to_page()\n returns rb-\u003eaux_pages[0]\n [4]: map it as VM_PFNMAP\n [5]: rb-\u003eaux_pgoff = 1\n\n munmap the page\n [6]: free rb-\u003eaux_pages[0]\n\nPages mapped as VM_PFNMAP have no refcount protection, so CPU 1 holds a\nmapping to a freed physical frame.\n\nFix this by taking rb-\u003eaux_mutex across the page walk in map_range()."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - Exploitation uses local perf_event_open(), ioctl(), mmap(), and munmap() operations; no network or physical path reaches map_range().\nAC:L - The attacker controls both racing mappings and the freeing munmap(), can enlarge the AUX allocation window, and can retry without depending on victim-controlled conditions.\nPR:L - An ordinary unprivileged user can create task-scoped AUX events such as Intel PT with exclude_kernel enabled under the upstream default perf_event_paranoid setting.\nUI:N - The attacking process independently creates the events, races the mappings, frees the AUX buffer, and accesses the stale mapping without victim action.\nS:U - Exploitation compromises the host kernel from local userspace but does not inherently cross a separate virtualization or IOMMU security authority.\nC:H - The persistent VM_PFNMAP alias exposes whichever kernel allocation reuses the freed physical frame, enabling disclosure of sensitive kernel memory.\nI:H - The stale page is mapped at offset zero, where pfn_mkwrite permits writes, enabling corruption of a reused kernel page and potential control-flow hijacking.\nA:H - Writing through the stale PFN can corrupt arbitrary kernel-owned page contents and cause an oops, panic, or complete system compromise."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T04:52:58.194Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/c8b7e113f7b61eef2f017e6329c27c2331058c5a"
},
{
"url": "https://git.kernel.org/stable/c/0cff05bd2186020f8706233e261016d149cc24db"
},
{
"url": "https://git.kernel.org/stable/c/5948aaf64f81f217a25dcc2bf6c0779bca19566c"
}
],
"title": "perf/aux: Fix page UAF in map_range()",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-64300",
"datePublished": "2026-07-25T08:49:36.372Z",
"dateReserved": "2026-07-19T15:36:31.778Z",
"dateUpdated": "2026-08-17T04:52:58.194Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-64300",
"date": "2026-09-24",
"epss": "0.00182",
"percentile": "0.06877"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"kernel/events/core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "c8b7e113f7b61eef2f017e6329c27c2331058c5a",
"status": "affected",
"version": "b709eb872e19a19607bbb6d2975bc264d59735cf",
"versionType": "git"
},
{
"lessThan": "0cff05bd2186020f8706233e261016d149cc24db",
"status": "affected",
"version": "b709eb872e19a19607bbb6d2975bc264d59735cf",
"versionType": "git"
},
{
"lessThan": "5948aaf64f81f217a25dcc2bf6c0779bca19566c",
"status": "affected",
"version": "b709eb872e19a19607bbb6d2975bc264d59735cf",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"kernel/events/core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.14"
},
{
"lessThan": "6.14",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.39",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.4",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "A14068C8-C11C-44AA-9581-F8861BC66FF8",
"versionEndExcluding": "6.18.39",
"versionStartIncluding": "6.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "6228DDD6-4557-4AA3-9F43-AB995D471E42",
"versionEndExcluding": "7.1.4",
"versionStartIncluding": "6.19",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:*",
"matchCriteriaId": "5E8B9085-7ADB-4A05-89EF-12949B6A0509",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.2:rc2:*:*:*:*:*:*",
"matchCriteriaId": "1FC0D50D-9D58-4947-A197-A5A3FF07E7E3",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf/aux: Fix page UAF in map_range()\n\nmap_range() reads rb-\u003eaux_pages[], rb-\u003eaux_nr_pages and rb-\u003eaux_pgoff via\nperf_mmap_to_page() while holding only event-\u003emmap_mutex. Those fields are\nserialized by rb-\u003eaux_mutex, and mmap_mutex is per event.\n\nThus, two events sharing one rb via PERF_EVENT_IOC_SET_OUTPUT can race\nrb_alloc_aux() with map_range(), leading to a page-UAF scenario as follows:\n\n CPU 0 CPU 1\n ===== =====\n rb_alloc_aux() map_range()\n [1]: allocate rb-\u003eaux_pages[0]\n [2]: rb-\u003eaux_nr_pages++\n [3]: perf_mmap_to_page()\n returns rb-\u003eaux_pages[0]\n [4]: map it as VM_PFNMAP\n [5]: rb-\u003eaux_pgoff = 1\n\n munmap the page\n [6]: free rb-\u003eaux_pages[0]\n\nPages mapped as VM_PFNMAP have no refcount protection, so CPU 1 holds a\nmapping to a freed physical frame.\n\nFix this by taking rb-\u003eaux_mutex across the page walk in map_range()."
}
],
"id": "CVE-2026-64300",
"lastModified": "2026-09-03T16:12:22.440",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"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",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9,
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary"
}
]
},
"published": "2026-07-25T10:17:10.930",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/0cff05bd2186020f8706233e261016d149cc24db"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/5948aaf64f81f217a25dcc2bf6c0779bca19566c"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/c8b7e113f7b61eef2f017e6329c27c2331058c5a"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-416"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Important",
"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",
"product_status:fixed": "309",
"product_status:known_not_affected": "198",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: perf/aux: Fix page UAF in map_range()",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64300.json",
"version": "3"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
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.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- 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.
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…