An issue was discovered in the proc_pid_stack function in fs/proc/base.c in the Linux kernel through 4.18.11. It does not ensure that only root may inspect the kernel stack of an arbitrary task, allowing a local attacker to exploit racy stack unwinding and leak kernel task stack contents.
https://usn.ubuntu.com/3880-2/
https://usn.ubuntu.com/3880-1/
https://usn.ubuntu.com/3871-5/
https://usn.ubuntu.com/3871-4/
https://usn.ubuntu.com/3871-3/
https://usn.ubuntu.com/3871-1/
https://usn.ubuntu.com/3835-1/
https://usn.ubuntu.com/3832-1/
https://usn.ubuntu.com/3821-2/
https://usn.ubuntu.com/3821-1/
https://support.f5.com/csp/article/K27673650?utm_source=f5support&%3Butm_medium=RSS
https://marc.info/?l=linux-fsdevel&m=153806242024956&w=2
https://lists.debian.org/debian-lts-announce/2019/04/msg00004.html
https://lists.debian.org/debian-lts-announce/2019/03/msg00034.html
https://lists.debian.org/debian-lts-announce/2019/03/msg00017.html
https://access.redhat.com/errata/RHSA-2019:2473
https://access.redhat.com/errata/RHSA-2019:0831
https://access.redhat.com/errata/RHSA-2019:0514
https://access.redhat.com/errata/RHSA-2019:0512
http://www.securityfocus.com/bid/105525
http://lists.opensuse.org/opensuse-security-announce/2019-05/msg00043.html