How to mitigate CVE-2021-33909 Sequoia with Falco – Linux filesystem privilege escalation vulnerability

CVE-2021-33909, known as Sequoia, is a high-severity privilege escalation vulnerability affecting Linux's file system, primarily due to an out-of-bounds write in the Linux kernel's seq_file interface. Disclosed in July 2021, it impacts several Linux distributions, including Ubuntu, Debian, and Fedora, and allows low-level privileged users to escalate to root privileges, potentially compromising sensitive data and system integrity. Mitigation involves installing patches when available, using host scanning to detect vulnerabilities, and employing tools like Falco to monitor for suspicious post-exploitation activities. Falco, an open-source project, can detect unexpected application behavior and send alerts through customizable rules, enhancing security by identifying unauthorized actions within affected systems. While no public exploit has been released, the vulnerability's potential impact underscores the importance of proactive detection and remediation efforts to protect against unauthorized access and data breaches.