# CVE-2026-27966: Langflow has Remote Code Execution in CSV Agent

> Attackers can execute arbitrary code on Langflow servers via prompt injection in the CSV Agent node due to hardcoded dangerous code settings.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 26 Feb 2026
- **Updated:** 28 Feb 2026
- **Also known as:** GHSA-3645-fxcv-hqr4, PYSEC-2026-376

## What is CVE-2026-27966?

CVE-2026-27966 is a critical code injection vulnerability in Langflow Langflow, published on 26 Feb 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. Prior to version 1.8.0, the CSV Agent node in Langflow hardcodes `allow_dangerous_code=True`, which automatically exposes LangChain’s Python REPL tool (`python_repl_ast`). As a result, an attacker can execute arbitrary Python and OS commands on the server via prompt injection, leading to full Remote Code Execution (RCE). Version 1.8.0 fixes the issue.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2026-27966?

3 open source packages ship an affected version, including langflow. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `langflow` | PyPI | All versions to 1.8.0rc2 | None |
| `langflow` | PyPI | All versions to 1.8.0rc2 | None |
| `langflow` | PyPI | All versions to 1.8.0rc2 | None |

Products: Langflow Langflow.

## How do I fix CVE-2026-27966?

No fix has been published for CVE-2026-27966 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-27966 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-27966 exists.

Public exploit code:

- Exploit Tools For new CVE (github_poc): https://github.com/Anon-Cyber-Team/CVE-2026-27966--RCE-in-Langflow
- Pre-auth RCE scanner for Langflow < 1.8.0 — Route Injection + Vertex Injection → Code Execution (CVSS 9.8) (github_poc): https://github.com/shinthink/CVE-2026-27966
- Langflow RCE (metasploit)

## 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-2026-27966 and fix it if it is affected.

What it is: CVE-2026-27966 is a critical code injection vulnerability in Langflow Langflow, published on 26 Feb 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-2026-27966 exists.

Affected packages and fixed versions:
- langflow (PyPI): affected all versions up to 1.8.0rc2; no fix listed
- langflow (PyPI): affected all versions up to 1.8.0rc2; no fix listed
- langflow (PyPI): affected all versions up to 1.8.0rc2; 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-2026-27966/ (Markdown: https://insights.sbomify.com/CVE-2026-27966/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-27966
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-27966
- OSV: https://osv.dev/vulnerability/CVE-2026-27966

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-27966/
Summaries are generated and may contain mistakes; the official description above is the record.