CVE-2021-31439 is a vulnerability that impacts the Linux kernel, which is the core of the Linux operating system. The vulnerability is caused by a race condition in the tty code, which can allow a local attacker to gain elevated privileges or cause a denial of service (DoS) attack on the affected system. The race condition occurs when two processes try to simultaneously launch a terminal session, leading to a buffer overflow and potential privilege escalation.
In May 2021, the vulnerability was discovered and reported to the Linux kernel security team. A patch was quickly developed and released to address the issue, which was included in the Linux kernel version 5.12.7. However, it should be noted that not all Linux distributions immediately updated their systems with this patch, leaving them potentially vulnerable to exploitation.
Exploitation of CVE-2021-31439 could have serious consequences, including unauthorized access to sensitive data, modification of system configurations or settings, and disruption of critical services through DoS attacks. Therefore, it is important for organizations and individuals using Linux systems to ensure that they have installed the latest updates and patches, and to remain vigilant for any signs of suspicious activity on their systems.