Execution whitelist

Hydra 1.4 deprecates resolving config-selected Python targets without an execution whitelist supplied by trusted Python code. This applies to both hydra.utils.instantiate() and Python logging configured by Hydra.

For the permanent security model and API guidance, see Execution whitelist.

Migrate an application

Add the expected application and logging targets to @hydra.main():

import hydra

@hydra.main(
    config_path="conf",
    config_name="config",
    execution_whitelist=("my_app.*",),
)
def my_app(cfg):
    ...

Hydra automatically permits targets used by its built-in logging configurations. Add application-defined handlers, formatters, filters, queues, and listeners explicitly.

Logging configuration remains trusted. The execution whitelist does not restrict where log files are written. Do not load logging configuration from untrusted sources.

Migrate direct calls

Pass expected targets to direct instantiate() calls:

from hydra.utils import instantiate

model = instantiate(
    cfg.model,
    _execution_whitelist_="my_app.models.*",
)

If a framework or helper calls instantiate() internally, wrap the call in a trusted scope:

from hydra.utils import execution_whitelist

with execution_whitelist("my_app.*"):
    framework_function(cfg)

Temporary legacy behavior

Hydra 1.4 warns when it resolves config-selected targets without an execution whitelist; this becomes an error in Hydra 1.5. The no-whitelist path retains Hydra's target blacklist as defense-in-depth.

If unrestricted resolution is intentional and all relevant configuration is trusted, pass UNSAFE_DISABLE_EXECUTION_CHECKS explicitly. This disables both whitelist and blacklist checks and should not be used as a routine migration. See Restricted targets for the implications of disabling these checks.