---
id: "CVE-2026-77819"
kind: "vulnerability"
aliases: ["CVE-2026-77819"]
title: "Langflow: authenticated users can overwrite arbitrary files on the server"
severity: "medium"
cvss: 6.5
epss: null
exploited: false
status: "open"
category: "ai-tooling"
products: []
ecosystems: []
tags: ["ai-apps", "ai-tooling", "langflow", "self-hosted"]
not_affected_if: ["no-user-accounts", "version-outside-range"]
published_at: "2026-10-29T16:18:52+00:00"
first_seen_at: "2026-10-29T16:26:01+00:00"
updated_at: "2026-10-29T16:31:18+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77819", "first_seen_at": "2026-10-29T16:26:01+00:00"}]
---

# Langflow: authenticated users can overwrite arbitrary files on the server

IBM Langflow OSS versions 1.0.0 through 1.12.3 fail to restrict file paths to their intended directory. A remote attacker with a valid account can overwrite arbitrary files on the server.

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

## How to check

- Check the installed Langflow version with `langflow --version` or `pip show langflow`, and see whether it falls in 1.0.0 through 1.12.3.
- Confirm whether user accounts can reach the server over the network, since an account is needed to exploit this.

## Fix

- Langflow OSS: move to a version later than `1.12.3`; the sources do not name the exact fixed release.

## Timeline

- 2026-10-29T16:26:01+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-77819

## From the sources

IBM Langflow OSS 1.0.0 through 1.12.3 could allow a remote authenticated attacker to overwrite arbitrary files due to improper limitation of a pathname to a restricted directory.

---

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