Threat Intelligence Database

CVE-2026-106440 is a high-severity vulnerability in the hydra-ecosystem hydra framework affecting versions from 1.2.0 up to but not including 1.3.0 and certain 1.4.0 development releases. It involves unsafe reflection where externally controlled input can be used to select and execute arbitrary Python code via the hydra-optuna-sweeper package's custom_search_space configuration. This allows an attacker with control over Optuna sweep configuration or command-line overrides to execute code with the application's privileges, bypassing trusted execution whitelists. The issue is fixed in hydra versions 1.3.0 and 1.4.0.dev10.

Hydra is a framework for elegantly configuring complex applications. From 1.3.4 until 1.3.7 and 1.4.0.dev10, Hydra stores legacy instantiate target blocklists and related execution-policy collections in mutable module-level state. An attacker who controls multiple sibling target entries can resolve hydra._internal.target_policy.UNCONTROLLED_EXECUTION_TARGETS.discard through instantiate(), remove a denied target, and then invoke that target because sibling nodes are processed in insertion order against the same modified policy. The mutation persists in process-global state and can enable code execution with the application's privileges, while a narrow execution whitelist supplied by trusted Python code is not bypassed by the reported direct mutation path. This issue is fixed in versions 1.3.7 and 1.4.0.dev10.