In an article published by Trail of Bits, it is stated that code coverage metrics can be misleading because they measure execution rather than verification. This can result in critically important parts of software remaining untested, posing a serious security threat.

Mutation testing revealed a critical vulnerability in the Arkis protocol that could have allowed attackers to drain funds. This vulnerability went unnoticed when using traditional code coverage metrics, highlighting the importance of employing more advanced testing methods to ensure software security.