Developer Finds Injection Flaw in Release Pipelines of Four Major Open Source Projects

A developer audited the GitHub Actions release workflows of roughly 25 open source projects and discovered a template-injection vulnerability in four of them, including crewAI, polybar, in-toto, and TEN Framework. The flaw stems from directly embedding GitHub context values like tag names into shell scripts or JavaScript blocks using ${{ }} expressions, which are substituted as raw text before the shell or interpreter parses the code. An attacker with push access could craft a malicious tag name or workflow input to execute arbitrary commands in the pipeline, potentially abusing credentials such as PyPI publishing tokens stored in the same job. The fix involves passing context values through environment variables rather than inline template expressions, ensuring they are treated as data rather than executable code. All four affected projects were notified via pull requests, and the researcher emphasized accurately scoping the severity, noting that exploitation required repository write access rather than being open to anonymous attackers.