Automation-controller: automation-controller-container: automation-controller: credential type env-injector deny-list omits process-hijacking variables (bash_env/ld_preload) allowing code execution in the execution environment

A flaw was found in Ansible Automation Platform's automation-controller. The custom
Credential Type environment-variable injector validates variable names against a
deny-list (an ANSIBLE_* prefix check plus a fixed ENV_BLOCKLIST) that omits
process-hijacking loader variables such as BASH_ENV, ENV, LD_PRELOAD, LD_LIBRARY_PATH,
PYTHONSTARTUP and GIT_SSH_COMMAND. Combined with the credential file injector, a
privileged user can write an attacker-controlled script into the execution environment
and point BASH_ENV at it, obtaining arbitrary code execution inside the
execution-environment container for any job that attaches a credential of that type.