The vulnerability stems from a cryptographic weakness in the custom component validation mechanism of IBM Langflow OSS. When the hardening mode is active, component code is verified using a truncated SHA‑256 hash; an attacker can craft code that collides with the truncated hash of a trusted template. Once the collision is achieved, the application accepts the component and executes its Python code, allowing the attacker to run arbitrary code within the Langflow process and potentially take full control of the instance.

IBM Langflow OSS versions 1.0.0 through 1.10.3 are affected. The vulnerability exists in the component generation, validation, and custom component handling features of the product.

The CVSS score of 8.8 indicates high severity. The EPSS score is not available, and the vulnerability is not listed in the CISA KEV catalog. Exploitation requires the attacker to be authenticated and to have access to create or upload custom components while hardening mode is enabled. The attack vector is inferred to be insider or privileged user activity, as authentication is a prerequisite. No public exploits are known, but the described mechanism allows a determined attacker to fully compromise the affected system.