I built a PR listener and ruleset to detect malicious code in CI/CD

In plain words

PRevent is a GitHub app that scans pull requests to detect malicious code and can notify or block them. It includes a companion Semgrep ruleset for detecting malicious patterns at any stage of CI/CD pipelines. The tool addresses a real attack vector where compromised code can execute with repository access. It is designed for development teams seeking to add security checks to their code review process without extensive configuration overhead.

written from the facts on this page · September 2026

From the sources

Prevent merging of malicious code in pull requests - apiiro/PRevent

A self-hosted GitHub app that listens for pull request events, scans them for malicious code, and comments detections directly on the pull request. Typically, security scans are run by workflow files. However, files can be modified, and when dealing with source modification attacks, should be avoided. A GitHub-app approach addresses this gap, ensuring the scan is not bypassed while providing better flexibility. The app's logic can be leveraged to run any scan. All you need is to add a scanner method to the scan logic . Currently, PRevent detects dynamic code execution and obfuscation, patterns found in nearly 100% of malicious code attacks reported to this day, while being rare in benign…from github.com

In the maker’s words, at launch

I built a GitHub app that detects it in pull requests, notifies or blocks them. Alongside it, I published a Semgrep ruleset for any stage of the CI/CD. I started this after getting frustrated by all the FUD around malicious code - lots of noise, little effort to solve it. Having said that, it's still a major…

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  GitHub2025 · github.com · ▲13

  Prevent merging of malicious code in pull requests and CI/CD

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