---
id: "CVE-2025-34291"
kind: "vulnerability"
aliases: ["CVE-2025-34291"]
title: "Langflow versions up to and including 1.6.9 contain a chained vulnerability that enables account takeover and remote\u2026"
severity: "critical"
cvss: 9.4
epss: null
exploited: true
status: "open"
category: "ai-tooling"
products: [{"name": "Langflow Langflow", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "langflow", "fixed": ["1.7.0"], "affected": "<= 1.6.9", "ecosystem": "pypi"}, {"name": "langflow", "fixed": [], "affected": "<= 1.6.9", "ecosystem": "vendor"}]
ecosystems: ["pypi", "vendor"]
tags: ["ai-tooling", "ai-workflows", "cors", "exploited", "langflow", "rce", "self-hosted"]
not_affected_if: ["managed-hosting", "no-browser-users", "version-1.7.0-or-later"]
published_at: "2025-12-05T23:15:47+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T23:44:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2025-34291", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "analyst", "url": null, "first_seen_at": "2026-10-23T20:36:41+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-34291", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# Langflow versions up to and including 1.6.9 contain a chained vulnerability that enables account takeover and remote…

Langflow <= 1.6.9 ships CORS allow_origins=* with credentials and a SameSite=None refresh-token cookie. Any webpage a logged-in user visits can call the refresh endpoint, get fresh tokens, and use the built-in code validation endpoint for RCE. Fixed in 1.7.0. CISA KEV lists it as exploited.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Langflow Langflow affected ? fixed ?
- pypi:langflow affected <= 1.6.9 fixed 1.7.0
- vendor:langflow affected <= 1.6.9 fixed ?

## How to check

Run 'pip show langflow' (or check the container image tag): versions <= 1.6.9 are vulnerable. Also check env vars: LANGFLOW_CORS_ORIGINS should list specific origins, not '*'; LANGFLOW_CORS_ALLOW_CREDENTIALS should be false if origins are '*'; LANGFLOW_REFRESH_SAME_SITE should be lax or strict. The maintainer notes the SameSite default may still be permissive after upgrade, so set it explicitly. Review logs for unexpected requests to /api/v1/validate/code.

## Fix

Upgrade to langflow >= 1.7.0. The maintainer recommends the latest stable release, which they give as 1.9.3. Set LANGFLOW_CORS_ORIGINS to your exact domains, set LANGFLOW_REFRESH_SAME_SITE=lax or strict, and restrict network access (VPN or trusted network). Rotate API keys and tokens stored in any instance that was exposed.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2025-34291
- 2026-10-23T20:36:41+00:00 analyst — GHSA-577h-p2hh-v4mv: langflow (pip) <= 1.6.9 affected, fixed in 1.7.0 (CORS hardened, PR #9744 per maintainer); maintainer gives env-var mitigations in issue #11465; KEV exploitation from CISA. No public PoC link verified; Obsidian writeup describes the chain.
- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2025-34291

## Documents

- [advisory] GHSA-577h-p2hh-v4mv Langflow CORS misconfiguration enables Account Takeover and RCE https://github.com/advisories/ghsa-577h-p2hh-v4mv
- [describes] Obsidian Security: CVE-2025-34291 writeup https://www.obsidiansecurity.com/blog/cve-2025-34291-critical-account-takeover-and-rce-vulnerability-in-the-langflow-ai-agent-workflow-platform
- [mitigation] Inquiry Regarding CVE-2025-34291 Patch (maintainer mitigation guidance) https://github.com/langflow-ai/langflow/issues/11465

## From the sources

Langflow versions up to and including 1.6.9 contain a chained vulnerability that enables account takeover and remote code execution. An overly permissive CORS configuration (allow_origins='*' with allow_credentials=True) combined with a refresh token cookie configured as SameSite=None allows a malicious webpage to perform cross-origin requests that include credentials and successfully call the refresh endpoint. An attacker-controlled origin can therefore obtain fresh access_token / refresh_token pairs for a victim session. Obtained tokens permit access to authenticated endpoints — including built-in code-execution functionality — allowing the attacker to execute arbitrary code and achieve full system compromise.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_