CVE-2026-43458

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.

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EPSS — Exploit Prediction

0.0001

Probability of exploitation

0.02%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/23a3ac2e2262a291498567418227b99e1f3606b1 https://git.kernel.org/stable/c/27e43356d0defb9fc7fa25265219a3ffeb7b3e98 https://git.kernel.org/stable/c/288598d80a068a0e9281de35bcb4ce495f189e2a https://git.kernel.org/stable/c/35b58d3bc716ebb9ebd10fe1cac8c1177242511c https://git.kernel.org/stable/c/52135420e9f75853ea0c6cea7b736e3e98495f7d https://git.kernel.org/stable/c/8460187b4852fd00bd1c76394358053f3fa4d089 https://git.kernel.org/stable/c/97a0bb491cae39478c6225381f14e9ac67b7bba7 https://git.kernel.org/stable/c/ca2ceba983bb23ea0202c2882d963253416654a3

Frequently Asked Questions

What is CVE-2026-43458? +

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.

How do I check if I'm vulnerable to CVE-2026-43458? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.