Kernel crash via unchecked TTY cdev deletion
Published Sep 17, 2026 · Updated Sep 17, 2026
Linux 4.3 TTY removal allows local users to crash kernel execution via a NULL-pointer dereference after failed device registration. In drivers/tty/tty_io.c, tty_unregister_device() passes driver->cdevs[index] to cdev_del() without checking whether registration allocated it. The retained serial port must subsequently be removed; attacker control over the preceding registration failure is undocumented.
Summary
What happened
Linux 4.3 TTY removal allows local users to crash kernel execution via a NULL-pointer dereference after failed device registration. In drivers/tty/tty_io.c, tty_unregister_device() passes driver->cdevs[index] to cdev_del() without checking whether registration allocated it. The retained serial port must subsequently be removed; attacker control over the preceding registration failure is undocumented.
The record
- CVE
- CVE-2026-90335
- Published
- Sep 17, 2026
- Updated
- Sep 17, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 17, 2026CVE publishedPublication date reported by the CVE source.
- Sep 17, 2026Record updatedLatest update available in the CVE record.
Exploitability
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Is a vulnerable build present?
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- Affected versionversion=4.3
- Affected versionversion=a3a10ce3429e5dee623ad5c8407ea58e204fcb0a <3dbf85ef40b6366ba15e882f7536cdc98bea579a
- Affected versionversion=a3a10ce3429e5dee623ad5c8407ea58e204fcb0a <c3b5623fd97648f2747444aa8932ae604662df93
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What is affected?
Published CVSS scores
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Attacks
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Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
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Technologies
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