Bugs can persist in open-source projects even after years of continuous fuzzing, as highlighted by the article on OSS-Fuzz. Despite the initiative's success in identifying thousands of vulnerabilities across over 1,300 projects, some mature projects still harbor serious flaws. GStreamer, for instance, has only 19% code coverage with just two active fuzzers, compared to OpenSSL’s 139 fuzzers and 93% coverage. This lack of coverage demonstrates that human oversight remains essential to monitor and enhance fuzzing efforts. Developers often underestimate the risks, assuming their projects are secure simply because they’re enrolled in OSS-Fuzz. Poppler, a PDF parsing library, illustrates another challenge. Although it has 16 fuzzers and 60% code coverage, it missed a critical remote code execution vulnerability due to reliance on external dependencies that are not fuzzed. Some libraries, like DjVuLibre, are included with the software but lack fuzzing coverage, leaving systems vulnerable. Exiv2, a library for managing image metadata, has also faced ongoing vulnerabilities despite being in OSS-Fuzz for over three years. This highlights a common oversight in fuzzing, where researchers focus on decoding rather than encoding, potentially missing critical vulnerabilities that can be exploited during background processes. The article outlines a five-step fuzzing workflow aimed at improving results through code preparation, coverage enhancement, and triaging. By removing checksums, reducing randomness, and writing new fuzzing harnesses, developers can optimize their fuzzing efforts. The iterative process of running fuzzers, checking coverage, and making improvements is crucial for discovering vulnerabilities that might otherwise remain hidden. This hands-on approach is vital for maintaining security in open-source software.