Kernel crash via rearmed 6pack transmit timer
Published Aug 29, 2022 · Updated Aug 2, 2024
Use-after-free in the Linux Kernel 6pack driver before 5.17-rc6 allows local users to crash the kernel through an emulated AX.25 device. During 6pack device teardown, sp_xmit_on_air can rearm a timer after sixpack_close synchronizes it, then pty_write dereferences a released tty_struct. Exploitation requires local syscall access and a kernel with 6pack support; successful triggering interrupts the entire host by crashing the kernel.
Summary
What happened
Use-after-free in the Linux Kernel 6pack driver before 5.17-rc6 allows local users to crash the kernel through an emulated AX.25 device. During 6pack device teardown, sp_xmit_on_air can rearm a timer after sixpack_close synchronizes it, then pty_write dereferences a released tty_struct. Exploitation requires local syscall access and a kernel with 6pack support; successful triggering interrupts the entire host by crashing the kernel.
The record
- CVE
- CVE-2022-1198
- Published
- Aug 29, 2022
- Updated
- Aug 2, 2024
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-416
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 29, 2022CVE publishedPublication date reported by the CVE source.
- Aug 2, 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=Fixed in kernel v5.17-rc6
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- syzbot sixpack_close C reproducerproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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