Race condition in Linux kernel - CVE-2017-1000405
Published: December 1, 2017 / Updated: June 17, 2021
Vulnerability identifier: #VU9520
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear
CVE-ID: CVE-2017-1000405
CWE-ID: CWE-362
Exploitation vector: Local access
Exploit availability:
Public exploit is available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to a race condition within touch_pmd() function in mmhugemem.c file when handling THPs. A local user can read read-only huge pages using the get_user_pages() function and overwrite arbitrary huge pages and files mapped via THP.
Successful exploitation of the vulnerability may allow an attacker to perform a denial of service (DoS) attack.
This vulnerability is a result of patch against a another privilege escalation vulnerability in Linux kernel known as Dirty Cow (CVE-2016-5195).
How to mitigate CVE-2017-1000405
Install a patch from vendor's repository:
https://github.com/torvalds/linux/commit/a8f97366452ed491d13cf1e44241bc0b5740b1f0
https://github.com/torvalds/linux/commit/a8f97366452ed491d13cf1e44241bc0b5740b1f0