Langflow webhook authentication bypass allows unauthenticated flow execution

What's on the official record

The OSV advisory GHSA-cf6m-vc3m-7cgm reports a CRITICAL vulnerability in the PyPI package langflow, in the agent_framework layer, aliased as CVE-2026-8505 and classified under CWE-306. The advisory states that a vulnerability in Langflow's webhook authentication logic allows unauthenticated users to trigger the execution of any flow. The system incorrectly bypasses API key validation when the WEBHOOK_AUTH_ENABLE configuration is set to False. The advisory names the fixed version as 1.9.1 and is dated 5 October 2026.

Assessment

For a platform or AI-stack owner, the record lets you check which langflow version is pinned and how webhook authentication is configured. The advisory states the fix is 1.9.1, so a deployment on an earlier version with WEBHOOK_AUTH_ENABLE set to False is on the affected side of the record. The record names no attacker, victim, or loss, so it supports a version and configuration check rather than an incident claim.

For a deal team, the record lets you scope diligence on any target that runs langflow by asking which version is pinned and how webhook authentication is configured. The advisory states the fix is 1.9.1, so a target on an earlier version with WEBHOOK_AUTH_ENABLE set to False is on the affected side of the record. The record names no named company, so it supports a diligence question rather than a finding about any specific counterparty.

What would change this call

A revised advisory that names a different fixed version, or a statement that the bypass is reachable with WEBHOOK_AUTH_ENABLE set to True, would change the version and configuration check.

What to check next

Confidence

Filed 25 October 2026 from the record dated 5 October 2026.

Sources

[1] Langflow: Unauthenticated Flow Execution via Webhook Authentication Bypass — https://github.com/advisories/GHSA-cf6m-vc3m-7cgm