Related Vulnerabilities: CVE-2017-1000364  

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.

Severity High

Remote No

Type Privilege escalation

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.

AVG-325 linux-lts 4.9.33-1 4.9.34-1 High Fixed

AVG-324 linux-zen 4.11.6-1 4.11.6-3 High Fixed

AVG-314 linux-hardened 4.11.6.b-1 4.11.6.d-1 High Fixed

AVG-313 linux 4.11.6-1 4.11.6-3 High Fixed

23 Jun 2017 ASA-201706-31 AVG-313 linux High privilege escalation

23 Jun 2017 ASA-201706-30 AVG-324 linux-zen High privilege escalation

22 Jun 2017 ASA-201706-28 AVG-314 linux-hardened High privilege escalation

https://www.qualys.com/2017/06/19/stack-clash/stack-clash.txt
https://git.kernel.org/linus/1be7107fbe18eed3e319a6c3e83c78254b693acb