Unauthenticated RCE in Langflow (CVE‑2026‑5027) Actively Exploited, Threatening AI Application Supply Chains
What It Is — A path‑traversal flaw in Langflow, an open‑source low‑code platform for building AI applications, allows an unauthenticated attacker to write files to arbitrary locations on the host filesystem. When combined with Langflow’s execution engine, this leads to remote code execution (RCE).
Exploitability — Active exploitation has been observed in the wild (VulnCheck). Public PoC scripts are circulating, and the vulnerability carries a CVSS v3.1 score of 8.8 (High). No official patch is available at the time of writing.
Affected Products – Langflow ≤ v0.9.5 (all deployments of the open‑source project, whether self‑hosted or offered as a managed service).
TPRM Impact – Organizations that embed Langflow in internal tooling, expose it as a SaaS offering, or rely on third‑party vendors that use Langflow are at risk of supply‑chain compromise, data leakage, and lateral movement into adjacent systems.
Recommended Actions –
- Immediately isolate any Langflow instances from the internet.
- Apply the temporary mitigation released by the project (restrict write permissions on the
uploads/directory and enforce strict input validation). - Conduct a forensic scan for newly created files or suspicious processes on affected hosts.
- Review contracts with vendors that ship Langflow‑based solutions; require proof of remediation or migration to a patched fork.
- Update your third‑party risk register to reflect the elevated risk score for Langflow‑related services.
Source: The Hacker News