Local privilege escalation via queued skb use-after-free
Published Feb 27, 2024 · Updated Aug 5, 2026
Use-after-free in the MHI core of Linux 5.12 through 5.12.2 allows local users to corrupt kernel memory via queued socket buffers. The mhi_queue function enqueues an skb while the device is in M3, then incorrectly returns an error, causing its caller to free the still-queued buffer. Local access to an MHI PCIe WWAN interface is required; reuse or later completion of the freed buffer enables kernel code execution or a panic.
Summary
What happened
Use-after-free in the MHI core of Linux 5.12 through 5.12.2 allows local users to corrupt kernel memory via queued socket buffers. The mhi_queue function enqueues an skb while the device is in M3, then incorrectly returns an error, causing its caller to free the still-queued buffer. Local access to an MHI PCIe WWAN interface is required; reuse or later completion of the freed buffer enables kernel code execution or a panic.
The record
- CVE
- CVE-2021-46969
- Published
- Feb 27, 2024
- Updated
- Aug 5, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-416, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 27, 2024CVE publishedPublication date reported by the CVE source.
- Aug 5, 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=5.12
- Affected versionversion=a8f75cb348fd52e7a5cf25991cdf9c89fb0cfd41 <0ecc1c70dcd32c0f081b173a1a5d89952686f271
- Affected versionversion=a8f75cb348fd52e7a5cf25991cdf9c89fb0cfd41 <a99b661c3187365f81026d89b1133a76cd2652b3
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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