# 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.

- **Severity:** High 8.5 (`CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 May 2026
- **Updated:** 26 May 2026
- **Also known as:** GHSA-cw25-2p92-7f75, PYSEC-2026-2957, ROOT-APP-PYPI-CVE-2026-3515

## 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 (Improper Neutralization of Argument Delimiters in a Command)

## Which versions are affected by CVE-2026-3515?

3 open source packages ship an affected version, including prefect.


| Package | Ecosystem | 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.

## Is CVE-2026-3515 being exploited?

There is no known exploitation of CVE-2026-3515 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-3515 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-3515 in the wild and no public exploit code.

Affected packages and fixed versions:
- prefect (PyPI): affected all versions up to 3.6.18; no fix listed
- prefect (PyPI): affected all versions up to 3.6.18; no fix listed
- prefect (PyPI): affected all versions up to 3.6.18; no fix listed

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-3515/ (Markdown: https://insights.sbomify.com/CVE-2026-3515/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3515
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3515
- OSV: https://osv.dev/vulnerability/CVE-2026-3515

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3515/
Summaries are generated and may contain mistakes; the official description above is the record.