Local kernel memory corruption via premature fd exposure
Published Jul 12, 2024 · Updated May 11, 2026
Use-after-free in Linux kernel CacheFiles allows local users to corrupt kernel memory by closing an exposed anonymous file descriptor. The on-demand path calls fd_install() before acquiring the cache reference and before copy_to_user() completes, so user space can close the descriptor while cleanup releases an unheld reference. Reachability requires local low-privileged access to an active CacheFiles on-demand daemon, and successful triggering corrupts kernel-managed cache memory.
Summary
What happened
Use-after-free in Linux kernel CacheFiles allows local users to corrupt kernel memory by closing an exposed anonymous file descriptor. The on-demand path calls fd_install() before acquiring the cache reference and before copy_to_user() completes, so user space can close the descriptor while cleanup releases an unheld reference. Reachability requires local low-privileged access to an active CacheFiles on-demand daemon, and successful triggering corrupts kernel-managed cache memory.
The record
- CVE
- CVE-2024-40913
- Published
- Jul 12, 2024
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-416, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 12, 2024CVE publishedPublication date reported by the CVE source.
- May 11, 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=5.19
- Affected versionversion=c8383054506c77b814489c09877b5db83fd4abf2 <4b4391e77a6bf24cba2ef1590e113d9b73b11039
- Affected versionversion=c8383054506c77b814489c09877b5db83fd4abf2 <b9f58cdae6a364a3270fd6b6a46e0fd4f7f8ce32
- Affected versionversion=c8383054506c77b814489c09877b5db83fd4abf2 <d2d3eb377a5d081bf2bed177d354a4f59b74da88
- Affected versionversion=c8383054506c77b814489c09877b5db83fd4abf2 <eac51d9daacd61dcc93333ff6a890cf3efc8c1c0
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
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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