---
title: "CVE-2026-33017: Langflow Code Injection Vulnerability"
url: https://erroneo.us/security/cve/CVE-2026-33017/
description: "CVE-2026-33017 (Langflow Langflow): Exploited in the wild (CISA KEV). Langflow is a tool for building and deploying AI-powered agents and workflows. In…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-03-20
date_modified: 2026-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-33017"
kev: true
cvss: 9.3
epss: 0.24755
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-33017: Langflow Code Injection Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Langflow Langflow. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2026-03-25, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-04-08 ; treat that as the outer limit, not the target.
- EPSS 24.8% , percentile 98: FIRST’s model estimates a 24.8% chance of exploitation activity in the next 30 days, higher than 98% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes langflow (PyPI) <= 1.8.2, fixed in 1.9.0 . Check your lockfile, including transitive dependencies.
- Editorial verdict: Act now. Langflow CVE-2026-9198: Exploited Unauthenticated RCE — Langflow is now the most repeatedly exploited AI-agent builder on CISA's list; any network-reachable instance below 1.10.1 should be patched today and checked for compromise.

## What it is

Langflow is a tool for building and deploying AI-powered agents and workflows. In versions prior to 1.9.0, the POST /api/v1/buildpublictmp/{flowid}/flow endpoint allows building public flows without requiring authentication. When the optional data parameter is supplied, the endpoint uses attacker-controlled flow data (containing arbitrary Python code in node definitions) instead of the stored flow data from the database. This code is passed to exec() with zero sandboxing, resulting in unauthenticated remote code execution. This is distinct from CVE-2025-3248, which fixed /api/v1/validate/code by adding authentication. The buildpublictmp endpoint is designed to be unauthenticated (for public flows) but incorrectly accepts attacker-supplied flow data containing arbitrary executable code. This issue has been fixed in version 1.9.0.

## Affected packages

- PyPI `langflow` <= 1.8.2 → fixed: 1.9.0

## Affected products (CVE record)

- langflow-ai langflow: < 1.9.0

## Severity

- GitHub_M CVSS 4.0: 9.3 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L`
- GitHub CVSS 4.0: 9.3 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:A`

## Exploitation

- CISA KEV: added 2026-03-25; federal due date 2026-04-08. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 24.75% probability of exploitation activity in the next 30 days; percentile 98.

## Sources

- [github.com](https://github.com/langflow-ai/langflow/releases/tag/1.8.2)
- [Listed in CISA KEV notes (github.com)](https://github.com/langflow-ai/langflow/security/advisories/GHSA-vwmf-pq79-vjvx)
- [GitHub Advisory GHSA-vwmf-pq79-vjvx](https://github.com/advisories/GHSA-vwmf-pq79-vjvx)
- [CVE.org record CVE-2026-33017](https://www.cve.org/CVERecord?id=CVE-2026-33017)
- [NVD entry CVE-2026-33017](https://nvd.nist.gov/vuln/detail/CVE-2026-33017)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-33017)
- [github.com](https://github.com/langflow-ai/langflow/commit/73b6612e3ef25fdae0a752d75b0fabd47328d4f0)
- [github.com](https://github.com/advisories/GHSA-rvqx-wpfh-mfx7)
- [sysdig.com](https://www.sysdig.com/blog/cve-2026-33017-how-attackers-compromised-langflow-ai-pipelines-in-20-hours)
- [medium.com](https://medium.com/@aviral23/cve-2026-33017-how-i-found-an-unauthenticated-rce-in-langflow-by-reading-the-code-they-already-dc96cdce5896)
- [github.com](https://github.com/langflow-ai/langflow/pull/12160)
- [github.com](https://github.com/langflow-ai/langflow/issues/12345)
- [cisa.gov](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-33017)

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Source page: https://erroneo.us/security/cve/CVE-2026-33017/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt