CVE-2026-3515: Prefect GitHub Integration Argument Injection Vulnerability
Summary
CVE-2026-3515: Prefect has an Argument Injection issue. Affects prefect versions < 3.6.18. No fix is published. How to fix ↓
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Background
Prefect is an open-source workflow orchestration tool designed to help users build, schedule, and monitor data workflows. It integrates with various services, including GitHub, to facilitate version control and collaboration. The Prefect GitHub integration allows users to manage GitHub repositories directly within their workflows. However, a critical vulnerability has been identified in this integration, specifically in the GitHubRepository block, which can lead to severe security risks.
Vulnerability Detail
A vulnerability exists in the GitHubRepository block of the prefect-github integration in Prefect version 3.6.18. This issue allows an attacker to inject arbitrary git command-line options through the reference field. The reference field is concatenated directly into a git clone command string without proper sanitization, which is then parsed by shlex.split(). This flaw can lead to Server-Side Request Forgery (SSRF), credential theft, or remote code execution (RCE). The vulnerability affects both the aget_directory() and get_directory() methods in the src/integrations/prefect-github/prefect_github/repository.py file. The issue does not impact GitLab and BitBucket integrations, which utilize a safer command construction method.
How To Fix
No fixed version is published for this vulnerability.
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Workaround
As a temporary workaround, avoid using the reference field in the GitHubRepository block until you can update to a patched version. If you must use it, ensure that the input is sanitized and does not contain any potentially harmful command-line options.
Conclusion
The Prefect GitHub integration vulnerability (CVE-2026-3515) poses significant security risks due to improper handling of the reference field, allowing for command injection. Users are strongly advised to update to a patched version to mitigate these risks and ensure the security of their workflows.
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FAQ
The CVSS score of this vulnerability is 8.5, indicating a high severity level.
The vulnerability affects Prefect version 3.6.18 and earlier versions.
Exploitation of this vulnerability could lead to Server-Side Request Forgery (SSRF), credential theft, or remote code execution (RCE).
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As a workaround, avoid using the reference field in the GitHubRepository block until you can upgrade to a patched version.
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