Vulnerability Trends across Open-Source AI-Attributed Code

Recent advances in large language models (LLMs) have led to widespread adoption of AI-coding tools and increasing deployment of AI-assisted code. While AI’s potential for programming productivity is becoming evident, the security of AI-attributed code is still poorly understood. In this work, we collect the largest set of in-the-wild AI-attributed code to date, examining 253,390 files containing AI-assisted code from seven tools and 9,544 human-written files from public GitHub repositories. Our analyses reveal significant differences in security-relevant CWE prevalence across programming languages and AI tools, with tool-specific differences varying by language. Additionally, human-written Python exhibited significantly higher security-relevant CWE prevalence than AI-attributed Python (21.08% vs 11.15%) and higher file-level CVSS severity. Ultimately, our results extend prior work showing that vulnerable AI-assisted code is making it into public repositories, indicating a need for stronger review practices and greater developer security awareness when using these tools.