Vulnerability discovered in Linux HDLC driver

This is Yamada from the Systems Department

The cause was a very old Linux kernel vulnerability announced on March 7th.
Primary source:
CVE-2017-2636

Race condition in drivers/tty/n_hdlc.c in the Linux kernel through 4.10.1 allows local users to gain privileges or cause a denial of service (double free) by
setting the HDLC line discipline.

HDLC (High-Level Data Link Control)
is a communication technology used for point-to-multipoint communication, such as modems and ISDN, which are no longer seen today

.

There is no need to worry because I don't use the modem
driver .

The n_hdlc kernel module will be automatically loaded when an application attempts to use the HDLC line discipline from userspace .

So it seems like you need to be careful

This page provides solutions

​# echo "install n_hdlc /bin/true" >> /etc/modprobe.d/disable-n_hdlc.conf

They have posted a solution to prevent the n_hdlc module from being loaded by restarting the computer as follows

This applies to Red Hat Enterprise Linux 6, 7 and Red Hat Enterprise MRG 2, so
be sure to check for these update patch releases.

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you're exhausted from dealing with vulnerabilities that are announced one after another, some help from us here and make your life easier!!