Kernel memory corruption via stale netfs folio dereference
Published Jul 24, 2026 · Updated Jul 24, 2026
Use-after-free in the Linux Kernel netfs subsystem allows remote attackers to corrupt kernel memory through timed filesystem reads. After NETFS_RREQ_IN_PROGRESS is cleared, netfs_unlock_abandoned_read_pages() reads the index of no_unlock_folio even though ownership has returned to the caller, leaving a stale folio reference; netfs_unlock_read_folio() has the same error. A victim must mount an attacker-controlled network filesystem; induced read failures and completion timing can expose or corrupt kernel memory, crash the kernel, or cause permanent page-lock hangs.
Summary
What happened
Use-after-free in the Linux Kernel netfs subsystem allows remote attackers to corrupt kernel memory through timed filesystem reads. After NETFS_RREQ_IN_PROGRESS is cleared, netfs_unlock_abandoned_read_pages() reads the index of no_unlock_folio even though ownership has returned to the caller, leaving a stale folio reference; netfs_unlock_read_folio() has the same error. A victim must mount an attacker-controlled network filesystem; induced read failures and completion timing can expose or corrupt kernel memory, crash the kernel, or cause permanent page-lock hangs.
The record
- CVE
- CVE-2026-64216
- Published
- Jul 24, 2026
- Updated
- Jul 24, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-416, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 24, 2026CVE publishedPublication date reported by the CVE source.
- Jul 24, 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=ee4cdf7ba857a894ad1650d6ab77669cbbfa329e <3866d015f33aeedf81338dd99154703bef33faef
- Affected versionversion=ee4cdf7ba857a894ad1650d6ab77669cbbfa329e <6080fa3ecfbb4448a3b47368629534c09b6ec750
- Affected versionversion=ee4cdf7ba857a894ad1650d6ab77669cbbfa329e <dbe556972100fabb8e5a1b3d2163831ff07b1e8e
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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Public exploit references
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Technologies
Your stack
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Your stack
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