Kernel memory disclosure and corruption via exFAT fragments
Published Jul 25, 2026 · Updated Jul 25, 2026
Out-of-bounds memory access in the Linux Kernel exFAT driver allows local users to read and corrupt kernel memory via a crafted image. In exfat_find_dir_entry(), each short TYPE_EXTEND fragment advances uniname by 15 characters while the guard counts only the shorter extracted length, moving reads and writes beyond p_uniname->name. The image must be mounted and traversed through pathname operations; low-privileged local access is sufficient where a storage broker permits loop-backed image mounts.
Summary
What happened
Out-of-bounds memory access in the Linux Kernel exFAT driver allows local users to read and corrupt kernel memory via a crafted image. In exfat_find_dir_entry(), each short TYPE_EXTEND fragment advances uniname by 15 characters while the guard counts only the shorter extracted length, moving reads and writes beyond p_uniname->name. The image must be mounted and traversed through pathname operations; low-privileged local access is sufficient where a storage broker permits loop-backed image mounts.
The record
- CVE
- CVE-2026-64296
- Published
- Jul 25, 2026
- Updated
- Jul 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- Unavailable
- 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?
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- Affected versionversion=5.7
- Affected versionversion=ca06197382bde0a3bc20215595d1c9ce20c6e341 <33c0b96d7e1672be1de0053786637ea46fb81507
- Affected versionversion=ca06197382bde0a3bc20215595d1c9ce20c6e341 <3a1230e7b043c62737b05a3e9275ca83a43ad20a
- Affected versionversion=ca06197382bde0a3bc20215595d1c9ce20c6e341 <727bf7783a2936ffd55c628dddfd69343e511dcf
- Affected versionversion=ca06197382bde0a3bc20215595d1c9ce20c6e341 <72a2589d82eb001c94b74bcfe6f9a599bd9bef60
- Affected versionversion=ca06197382bde0a3bc20215595d1c9ce20c6e341 <c8e041c68c0bbb73aa62371ee63947bb6949d8b2
- Affected versionversion=ca06197382bde0a3bc20215595d1c9ce20c6e341 <ce4736c1e6c4cfbf1ac409a8c328a0b69546c9a0
- Affected versionversion=ca06197382bde0a3bc20215595d1c9ce20c6e341 <cf85180b8a015029ee147694eaf4e0b3537e9432
- Affected versionversion=ca06197382bde0a3bc20215595d1c9ce20c6e341 <fae76a94b35ee8c0e2eb6f64caca01d75c6d34e4
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Public exploit references
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Technologies
Your stack
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Your stack
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