CVE-2026-98751: tty: abort break signalling on hangup

Published Oct 18, 2026

Updated

In the Linux kernel, the following vulnerability has been resolved:

tty: abort break signalling on hangup

The break ioctls can race with hangup and end up calling into a tty driver for a device that is already gone or powered down.

Drivers must handle this race, but TCSBRK and TCSBRKP should still be aborted to avoid calling back into the driver after a user-controlled timeout (possibly even after the tty has been reopened).

Note that drivers should disable any break state on shutdown so just return on hangup (calling breakctl() again is racy and will most likely fail for drivers handling the race).

Affected Software

1 affected component

Linux Linux kernel

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Compensating control
Update tty drivers to disable any break state during shutdown, and abort TCSBRK/TCSBRKP break signalling on hangup so the ioctls return without calling back into a device that is gone or powered down.

Event History

Oct 18, 2026

CVE Published

via MITRE·03:47 PM

Data Sourced

via MITRE·03:47 PM

Description

Data Sourced

via NVD·04:17 PM

Description

Frequently Asked Questions

What conditions are needed to trigger this issue?

A process must issue the TCSBRK or TCSBRKP break ioctl while the associated TTY is being hung up. The race can otherwise allow a delayed callback into a driver after the device has gone away or been powered down, including after a user-controlled timeout.

Which systems are realistically exposed?

Linux systems using TTY devices and drivers are relevant when applications can invoke TCSBRK or TCSBRKP concurrently with device hangup. The provided information does not identify particular TTY drivers or configurations.

What behavior does the fix introduce?

The fix aborts pending break signalling when hangup occurs, rather than calling the driver again. Drivers are expected to disable any break state during shutdown; attempting another break_ctl() call during hangup is described as racy and likely to fail.

CVE-2026-98751: tty: abort break signalling on hangup

Affected Software

Remediation

Event History

Frequently Asked Questions

What conditions are needed to trigger this issue?

Which systems are realistically exposed?

What behavior does the fix introduce?

Company

Resources

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Frequently Asked Questions

What conditions are needed to trigger this issue?

Which systems are realistically exposed?

What behavior does the fix introduce?