CVE-2017-2636

Source
Severity High
Remote No
Type Privilege escalation
Description
A race condition flaw was found in the N_HLDC Linux kernel driver when accessing the n_hdlc.tbuf list that can lead to double free. A local, unprivileged user able to set the HDLC line discipline on the tty device could use this flaw to crash the system or increase their privileges on the system.
Group Package Affected Fixed Severity Status Ticket
AVG-203 linux-zen 4.10.1-1 4.10.2-1 High Fixed FS#53242
AVG-201 linux-grsec 1:4.9.13.r201702261126-1 1:4.9.14.r201703121245-1 High Fixed FS#53242
AVG-200 linux-lts 4.9.13-1 4.9.14-1 High Fixed FS#53242
AVG-192 linux 4.10.1-1 4.10.2-1 High Fixed FS#53242
Date Advisory Group Package Severity Description
14 Mar 2017 ASA-201703-8 AVG-192 linux High privilege escalation
13 Mar 2017 ASA-201703-7 AVG-201 linux-grsec High privilege escalation
12 Mar 2017 ASA-201703-6 AVG-200 linux-lts High privilege escalation
16 Mar 2017 ASA-201703-13 AVG-203 linux-zen High privilege escalation
References
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=82f2341c94d270421f383641b7cd670e474db56b
http://seclists.org/oss-sec/2017/q1/569
Notes
Workaround: # echo "install n_hdlc /bin/true" >> /etc/modprobe.d/disable-n_hdlc.conf
Patch: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=82f2341c94d270421f383641b7cd670e474db56b
Introduced by: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=be10eb7589337e5defbe214dae038a53dd21add8