The Checkmk - Remote Code Execution by Chaining Multiple Bugs series highlights a critical vulnerability in the NagVis integration with Checkmk, which can be chained together to gain remote code execution. The arbitrary file read vulnerability in NagVis allows an attacker to access sensitive files and delete them, leading to authentication bypass and further exploitation of a code injection vulnerability in Checkmk's watolib. This series emphasizes the importance of applying security on all layers, addressing vulnerabilities proactively, and ensuring that sensitive data is not stored in plaintext. The patches for these vulnerabilities were released as part of NagVis 1.9.34 and Checkmk version 2.1.0p11, respectively.