Local code execution via splice reference undercount
Published Jan 11, 2023 · Updated Aug 3, 2024
Use-after-free in Linux Kernel 5.7-rc1 through 5.10.159 allows local users to execute arbitrary code or crash the system via io_uring. The IORING_OP_SPLICE preparation path omits IO_WQ_WORK_FILES, so a splice involving a file that calls get_uts() uses current->nsproxy without first increasing its reference count and later decrements it into a dangling lifetime. Low-privileged local access is required, and successful exploitation permits kernel-context code execution or a system crash.
Summary
What happened
Use-after-free in Linux Kernel 5.7-rc1 through 5.10.159 allows local users to execute arbitrary code or crash the system via io_uring. The IORING_OP_SPLICE preparation path omits IO_WQ_WORK_FILES, so a splice involving a file that calls get_uts() uses current->nsproxy without first increasing its reference count and later decrements it into a dangling lifetime. Low-privileged local access is required, and successful exploitation permits kernel-context code execution or a system crash.
The record
- CVE
- CVE-2022-4696
- Published
- Jan 11, 2023
- Updated
- Aug 3, 2024
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-763, CWE-416, CAPEC-251, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jan 11, 2023CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record 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=5.7-rc1 <=5.10.159
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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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