CVE-2026-64267

System crash via wrapped FUSE prune count

Published Jul 25, 2026 · Updated Jul 25, 2026

Integer overflow in Linux Kernel 6.18 through 6.18.38 and 6.19 through 7.1.3 allows local users to crash the kernel via FUSE pruning. The FUSE_NOTIFY_PRUNE length check multiplies a daemon-controlled count in 32-bit size_t arithmetic, allowing a wrapped result to admit an absent nodeid array into the copy loop. Exploitation requires control of a FUSE daemon on a 32-bit kernel; the malformed notification reaches a kernel BUG and interrupts service.

CVSS severity5.5
Medium
EPSS probability0.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer overflow in Linux Kernel 6.18 through 6.18.38 and 6.19 through 7.1.3 allows local users to crash the kernel via FUSE pruning. The FUSE_NOTIFY_PRUNE length check multiplies a daemon-controlled count in 32-bit size_t arithmetic, allowing a wrapped result to admit an absent nodeid array into the copy loop. Exploitation requires control of a FUSE daemon on a 32-bit kernel; the malformed notification reaches a kernel BUG and interrupts service.

The record

CVE
CVE-2026-64267
Published
Jul 25, 2026
Updated
Jul 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3f29d59e92a96d843c2ff10ebfed92ac26878658 <54243797cedf55447b4c5d560e8cd709900061ae
  2. Affected versionversion=3f29d59e92a96d843c2ff10ebfed92ac26878658 <6e2d84fdeac05bfd858e84a76353fdb84f23a43e
  3. Affected versionversion=3f29d59e92a96d843c2ff10ebfed92ac26878658 <c78c4b242299bc581e4987e5c2786c6f4760c516
  4. Affected versionversion=6.18

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=3f29d59e92a96d843c2ff10ebfed92ac26878658 <54243797cedf55447b4c5d560e8cd709900061ae; version=3f29d59e92a96d843c2ff10ebfed92ac26878658 <6e2d84fdeac05bfd858e84a76353fdb84f23a43e; version=3f29d59e92a96d843c2ff10ebfed92ac26878658 <c78c4b242299bc581e4987e5c2786c6f4760c516; version=6.18

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5Amazon LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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