CVE-2026-3515 Argument Injection in prefecthq/prefect
Attackers can inject git options via the reference field in Prefect's GitHub integration, leading to SSRF, credential theft, or remote code execution.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-3515?
CVE-2026-3515 is a high-severity command injection vulnerability in prefecthq/prefect, published on 24 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A vulnerability in the `GitHubRepository` block of the `prefect-github` integration in Prefect version 3.6.18 allows an attacker to inject arbitrary git command-line options via the `reference` field. The `reference` field is concatenated directly into a `git clone` command string without proper sanitization, and then parsed by `shlex.split()`. This enables injection of options such as `-c`, leading to potential Server-Side Request Forgery (SSRF), credential theft, or remote code execution (RCE). The vulnerability affects both the `aget_directory()` and `get_directory()` methods in `src/integrations/prefect-github/prefect_github/repository.py`. This issue does not affect the GitLab and BitBucket integrations, which use a safer list-based command construction approach.
Weakness: CWE-88
Which versions are affected by CVE-2026-3515?
3 open source packages ship an affected version, including prefect.
| Package | Affected | Fixed in |
|---|---|---|
prefect PyPI | All versions to 3.6.18 | None |
prefect PyPI | All versions to 3.6.18 | None |
prefect PyPI | All versions to 3.6.18 | None |
How do I fix CVE-2026-3515?
Apply the vendor's patch.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-3515 being exploited?
There is no known exploitation of CVE-2026-3515 in the wild and no public exploit code.
Sources
Also known as GHSA-cw25-2p92-7f75, PYSEC-2026-2957, ROOT-APP-PYPI-CVE-2026-3515.