# 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 ...

Advisory record · `GHSA-577h-p2hh-v4mv`

- **Identifiers:** `GHSA-577h-p2hh-v4mv` · `CVE-2025-34291` · `PYSEC-2025-78`
- **State:** Confirmed
- **Severity:** CVSS 9.4 Critical
- **Critical:** Yes: KEV, CVSS 9+, CVSS 7+ and EPSS
- **Weakness (CWE):** [CWE-346](https://cwe.mitre.org/data/definitions/346.html)
- **Tags:** [CWE-346](https://agentprime.io/advisories/tag/cwe-346.md)
- **Published:** 5 Dec 2025
- **Updated:** 10 Jun 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 5 Dec 2025, 23:15 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Critical

Critical, because:

- In CISA’s KEV catalogue since 21 May 2026: it is known to be exploited.
- CVSS score 9.4: 9.0 or more.
- CVSS score 9.4 (7.0 or more) and EPSS 0.93 (0.1 or more): a high score and a real chance of exploitation in the next 30 days.

How we decide what’s critical: <https://agentprime.io/advisories/critical.md>

## Affected packages

- `langflow` (PyPI): affected `<1.7.0`; fixed in `1.7.0`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> Langflow versions up to and including 1.6.9 are vulnerable. A victim who visits a malicious webpage while logged in can have their session refreshed by that page, letting an attacker obtain access and refresh tokens. The attacker can then reach authenticated features, including built-in code execution, to run arbitrary code on the system. Upgrade to Langflow 1.7.0 or later.

Written 10 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 9.4 Critical, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`, from CNA (VulnCheck)

- **CISA KEV:** Listed since 21 May 2026: known to be exploited.
- **EPSS:** 0.93, the 99th percentile, on 11 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

This record came from the full history of the GitHub Advisory Database, published 5 Dec 2025. New records show when each source confirmed them.

## Sources

- [GitHub Advisory Database: GHSA-577h-p2hh-v4mv](https://github.com/advisories/GHSA-577h-p2hh-v4mv)
- [OSV: GHSA-577h-p2hh-v4mv](https://osv.dev/vulnerability/GHSA-577h-p2hh-v4mv)
- <https://www.vulncheck.com/advisories/langflow-cors-misconfiguration-to-token-hijack-and-rce>
- <https://github.com/langflow-ai/langflow>
- <https://github.com/advisories/GHSA-577h-p2hh-v4mv>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-577h-p2hh-v4mv>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-577h-p2hh-v4mv/>. Everything for agents: <https://agentprime.io/llms.txt>.