Langflow is one of the tools people use to 'click together' AI agents with no code. Boxes, arrows, done. That's exactly why this hole hurts so much: there are a lot of installs, and their owners rarely follow security bulletins.
Fact
The facts: CVE-2026-9198 affects Langflow OSS from version 1.0.0 through 1.10.0 inclusive, scored 9.8 out of a maximum 10. The chain is two unauthenticated API endpoints: /api/v1/auto_login issues a SUPERUSER token, and /api/v1/validate/code executes submitted code - on a default install that means remote code execution with full privileges, no password at all. The vulnerability was published on 17 July, and on 4 August CISA added it to the KEV catalog of actively exploited vulnerabilities - the patch deadline for US federal agencies is 7 August, three days. The fix: version 1.10.1 or later. Sources: NVD and CISA KEV, 04.08.2026.
One thing I keep asking: how many of these installs even have an owner? Langflow gets spun up for an afternoon - a demo for the boss, an intern's experiment, a prototype to 'see if it works'. Then the demo keeps running on a server with a public address, and everyone forgets about it. Low-code AI builders became infrastructure without going through the discipline of infrastructure. Nobody puts 'patch every month' on their calendar for them.
And the second layer: these systems hold keys by definition. A Langflow install with no API keys to models and databases is a rarity, so a compromised install is not just another machine. It's a connection to everything the demo has ever touched.
The demo nobody remembers is the door everyone is looking for.
Check today: if you or a client is running Langflow, bump the version to 1.10.1 right away, and public access goes behind a VPN or at least proxy-level authentication. And one thing to remember for every AI demo from here on - either it has an owner and a patch calendar, or it gets switched off.
Sources
NVD - CVE-2026-9198 (Langflow code injection), record as of 04.08.2026CISA - Known Exploited Vulnerabilities CatalogThe visual is generated code-art, no third-party images.