SB2018012512 - Red Hat update for Linux Kernel
Published: January 25, 2018 Updated: December 15, 2022
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Race condition (CVE-ID: CVE-2017-1000405)
CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CVSSv4: 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
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).
2) Privilege escalation (CVE-ID: CVE-2016-5195)
CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Green
The vulnerability allows a local user to obtain elevated privileges on the target system.
The weakness is due to race condition in the kernel memory subsystem in the management of copy-on-write operations on read-only memory mappings that lets attackers to overwrite kernel memory and gain kernel-level privileges.
Successful exploitation of the vulnerability results in gaining of root privileges on the vulnerable system.
Note: the vulnerability was being actively exploited.
Remediation
Install update from vendor's website.