Subject: [ASA-201706-30] linux-zen: privilege escalation Arch Linux Security Advisory ASA-201706-30 ========================================== Severity: High Date : 2017-06-23 CVE-ID : CVE-2017-1000364 Package : linux-zen Type : privilege escalation Remote : No Link : https://security.archlinux.org/AVG-324 Summary ======= The package linux-zen before version 4.11.6-3 is vulnerable to privilege escalation. Resolution ========== Upgrade to 4.11.6-3. # pacman -Syu "linux-zen>=4.11.6-3" The problem has been fixed upstream but no release is available yet. Workaround ========== None. Description =========== A flaw was found in the way memory was being allocated on the stack for user space binaries. If heap (or different memory region) and stack memory regions were adjacent to each other, an attacker could use this flaw to jump over the stack guard gap, cause controlled memory corruption on process stack or the adjacent memory region, and thus increase their privileges on the system. This is a kernel-side mitigation which increases the stack guard gap size from one page to 1 MiB to make successful exploitation of this issue more difficult. Impact ====== A local attacker is able to bypass the stack guard for user space binaries effectively leading to elevation of privileges by choosing a suitable target application. References ========== https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt https://git.kernel.org/linus/1be7107fbe18eed3e319a6c3e83c78254b693acb https://security.archlinux.org/CVE-2017-1000364