File corruption via stale netfs folio tracking
Published Jul 19, 2026 · Updated Jul 19, 2026
Data corruption in Linux Kernel allows local users to corrupt CIFS file contents through overlapping streaming writes. In netfs_perform_write(), a successful full-folio overwrite leaves the prior netfs_folio dirty-region record attached, while a partial copy can overwrite recorded dirty data without updating that record. The defect requires a writable CIFS mount using the default cache option and a write pattern that replaces all or part of a partially written streaming-write folio.
Summary
What happened
Data corruption in Linux Kernel allows local users to corrupt CIFS file contents through overlapping streaming writes. In netfs_perform_write(), a successful full-folio overwrite leaves the prior netfs_folio dirty-region record attached, while a partial copy can overwrite recorded dirty data without updating that record. The defect requires a writable CIFS mount using the default cache option and a write pattern that replaces all or part of a partially written streaming-write folio.
The record
- CVE
- CVE-2026-64063
- Published
- Jul 19, 2026
- Updated
- Jul 19, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1565.001
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 19, 2026CVE publishedPublication date reported by the CVE source.
- Jul 19, 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=6.12
- Affected versionversion=8f52de0077ba3bf41e5d53d67a185700f41efce7 <20195925c768626dc901a4781a51e508702c88ad
- Affected versionversion=8f52de0077ba3bf41e5d53d67a185700f41efce7 <7b4dcf1b9455a6e52ac7478b4057dbe10359576d
- Affected versionversion=8f52de0077ba3bf41e5d53d67a185700f41efce7 <cdae00e8e215d95911d95f100599e187b6560de5
- Affected versionversion=8f52de0077ba3bf41e5d53d67a185700f41efce7 <ef9b521212e4863814ef7dfe19889abaf55ca840
What conditions does exploitation require?
What is affected?
Published CVSS scores
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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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