Kernel use-after-free via exiting SMB session traversal
Published Apr 28, 2024 · Updated May 11, 2026
Use-after-free in the Linux SMB client allows local users to corrupt kernel memory by reading open_files during session teardown. cifs_debug_files_proc_show() traverses an SMB session's connection and open-file lists after the session enters SES_EXITING, allowing teardown to free an object that the procfs reader still dereferences. The open_files entry is mode 0400, so the read requires administrative access and concurrent SMB session teardown; the kernel record documents no demonstrated exploit outcome.
Summary
What happened
Use-after-free in the Linux SMB client allows local users to corrupt kernel memory by reading open_files during session teardown. cifs_debug_files_proc_show() traverses an SMB session's connection and open-file lists after the session enters SES_EXITING, allowing teardown to free an object that the procfs reader still dereferences. The open_files entry is mode 0400, so the read requires administrative access and concurrent SMB session teardown; the kernel record documents no demonstrated exploit outcome.
The record
- CVE
- CVE-2024-26928
- Published
- Apr 28, 2024
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-416
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Apr 28, 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=4.20
- Affected versionversion=dfe33f9abc08997e56f9bdf14fe9ac7ac0e14075 <229042314602db62559ecacba127067c22ee7b88
- Affected versionversion=dfe33f9abc08997e56f9bdf14fe9ac7ac0e14075 <3402faf78b2516b0af1259baff50cc8453ef0bd1
- Affected versionversion=dfe33f9abc08997e56f9bdf14fe9ac7ac0e14075 <8f8718afd446cd4ea3b62bacc3eec09f8aae85ee
- Affected versionversion=dfe33f9abc08997e56f9bdf14fe9ac7ac0e14075 <a140224bcf87eb98a87b67ff4c6826c57e47b704
- Affected versionversion=dfe33f9abc08997e56f9bdf14fe9ac7ac0e14075 <a65f2b56334ba4dc30bd5ee9ce5b2691b973344d
- Affected versionversion=dfe33f9abc08997e56f9bdf14fe9ac7ac0e14075 <ca545b7f0823f19db0f1148d59bc5e1a56634502
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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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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