CVE-2018-16550 is a vulnerability that affects Linux kernel versions 4.9 and higher. It stems from a race condition in the fasync() function, which is responsible for managing asynchronous file operations. An attacker with local access to a vulnerable system may exploit this flaw to escalate their privileges and gain root access. This vulnerability was discovered by security researchers at Tencent Keen Security Lab in April 2018.
In August 2018, Red Hat released a security advisory detailing the impact of CVE-2018-16550 and providing updates to address the vulnerability. The advisory rated the severity of the vulnerability as important, warning that a successful exploit could allow an attacker to execute arbitrary code, modify files, or cause a denial-of-service condition. Several other Linux distributions, including Debian, Ubuntu, and SUSE, also released updates to address the vulnerability around the same time.
It is worth noting that while CVE-2018-16550 can be exploited locally, an attacker must already have some level of access to the affected system to do so. As such, organizations are advised to practice good security hygiene and limit local user privileges to reduce the likelihood of an attacker being able to exploit this or similar vulnerabilities.