Hydra’s Optuna sweeper allowed a configuration value to be interpreted as a dotted path, which was resolved with hydra.utils.get_method() and executed inside the Hydra controller process without the safety checks applied by instantiate(). An attacker able to influence the Optuna sweep configuration or command‑line overrides could therefore point the configuration to any importable Python object and cause it to run with the application’s privileges, effectively bypassing any execution whitelist that newer releases are intended to enforce.

The vulnerable product is Hydra from hydra‑ecosystem. Versions from 1.2.0 up to and including 1.3.0, as well as the development release 1.4.0.dev10, contain the flaw. The fix was incorporated in release 1.3.0 and in 1.4.0.dev10.

The CVSS score of 7.8 signals a significant code‑execution weakness. The EPSS score is not available, and the vulnerability is not listed in the CISA KEV catalog, making the broader exploitation probability unclear. Because the flaw is exercised through a configuration setting that an attacker can alter, the likely attack vector involves tampering with the Optuna sweep configuration or command‑line overrides so that hydra.sweeper.custom_search_space resolves to an untrusted callable, which is then executed in the Hydra controller process.