Local kernel code execution via FUSE request race
Published Jul 25, 2026 · Updated Jul 25, 2026
Use-after-free in the Linux kernel FUSE subsystem allows local users to execute kernel code or crash the system through a FUSE race. fuse_ref_folio() unlocks a request and returns without re-locking it, letting an abort callback free its arguments before later copy-chain code dereferences them. An unprivileged FUSE mount owner must coordinate writeback, splice processing, and connection abort; successful exploitation compromises the kernel or interrupts the host.
Summary
What happened
Use-after-free in the Linux kernel FUSE subsystem allows local users to execute kernel code or crash the system through a FUSE race. fuse_ref_folio() unlocks a request and returns without re-locking it, letting an abort callback free its arguments before later copy-chain code dereferences them. An unprivileged FUSE mount owner must coordinate writeback, splice processing, and connection abort; successful exploitation compromises the kernel or interrupts the host.
The record
- CVE
- CVE-2026-64266
- Published
- Jul 25, 2026
- Updated
- Jul 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-825, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 25, 2026CVE publishedPublication date reported by the CVE source.
- 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.
- Affected versionversion=2.6.35
- Affected versionversion=c3021629a0d820247ee12b6c5192a1d5380e21c6 <0e4a5a000123d81234e27a2f8187688cf608f755
- Affected versionversion=c3021629a0d820247ee12b6c5192a1d5380e21c6 <1ca605cfa59377f0143fb35b5b01360f37d1b7c4
- Affected versionversion=c3021629a0d820247ee12b6c5192a1d5380e21c6 <1f9156714592356b4fda57beac7eab9c2a462dd3
- Affected versionversion=c3021629a0d820247ee12b6c5192a1d5380e21c6 <5630da218a45ba80f0aba0846cbe8aa655da122b
- Affected versionversion=c3021629a0d820247ee12b6c5192a1d5380e21c6 <65a1c2551f7e16085acbb54aedde1feaa559ba7a
- Affected versionversion=c3021629a0d820247ee12b6c5192a1d5380e21c6 <b5befa80fdbe287a98480effed9564712924add5
- Affected versionversion=c3021629a0d820247ee12b6c5192a1d5380e21c6 <be353caffa8640f5e25fb3714ce8b0cef5e410e5
- Affected versionversion=c3021629a0d820247ee12b6c5192a1d5380e21c6 <e6aa539720c3d8def69683ed0c07cf9faea4e8be
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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