CVE-2026-17627

IBM Langflow OSS versions 1.0.0 through 1.10.2 contain an improper authorization flaw (CWE-639) in which the application fails to correctly verify a user's permission to access specific workflow resources. A remote attacker with any valid low-privileged account can send crafted network requests to bypass the missing authorization checks. Successful exploitation allows the attacker to read sensitive information and inject attacker-controlled messages into workflow history, with no impact on availability. All Langflow OSS deployments running 1.0.0 through 1.10.2 are affected, though the requirement for an authenticated account reduces exposure for instances with a small user base. There is currently no known public proof of concept, the flaw is not in CISA's KEV catalog, and EPSS estimates only about a 0.2% probability of exploitation in the next 30 days.

What to do: Upgrade Langflow to a fixed release newer than 1.10.2, following IBM's advisory for the exact patched version. Until patched, limit which accounts can reach the Langflow service, restrict its network exposure, and audit workflow history for unexpected or injected messages. Because exploitation requires valid credentials, also review and revoke unused or over-privileged accounts.