CVE-2026-106441: Hydra logging configuration permits unsafe callable resolution

Hydra passed its Python logging configuration to logging.config.dictConfig(). Python’s logging configurator can resolve and invoke importable classes and factories named by configuration, including handler class values and formatter, filter, handler, queue, and listener () factories.

This logging path was not mediated by Hydra’s target policy. In versions that already protected instantiate(), logging resolution bypassed those controls because it did not use instantiate().

An attacker who can control a Hydra logging configuration can use a custom class or factory to execute code with the application’s privileges when Hydra configures logging.