CVE-2026-43458

high

Description

In the Linux kernel, the following vulnerability has been resolved: serial: caif: hold tty->link reference in ldisc_open and ser_release A reproducer triggers a KASAN slab-use-after-free in pty_write_room() when caif_serial's TX path calls tty_write_room(). The faulting access is on tty->link->port. Hold an extra kref on tty->link for the lifetime of the caif_serial line discipline: get it in ldisc_open() and drop it in ser_release(), and also drop it on the ldisc_open() error path. With this change applied, the reproducer no longer triggers the UAF in my testing.

References

https://git.kernel.org/stable/c/ca2ceba983bb23ea0202c2882d963253416654a3

https://git.kernel.org/stable/c/97a0bb491cae39478c6225381f14e9ac67b7bba7

https://git.kernel.org/stable/c/8460187b4852fd00bd1c76394358053f3fa4d089

https://git.kernel.org/stable/c/52135420e9f75853ea0c6cea7b736e3e98495f7d

https://git.kernel.org/stable/c/35b58d3bc716ebb9ebd10fe1cac8c1177242511c

https://git.kernel.org/stable/c/288598d80a068a0e9281de35bcb4ce495f189e2a

https://git.kernel.org/stable/c/27e43356d0defb9fc7fa25265219a3ffeb7b3e98

https://git.kernel.org/stable/c/23a3ac2e2262a291498567418227b99e1f3606b1

Details

Source: Mitre, NVD

Published: 2026-05-08

Updated: 2026-05-08

Risk Information

CVSS v2

Base Score: 7.2

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 7.1

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

Severity: High