Bash CVE-2019-18276: Restricted Shell Bypass via Implicit Builtin Loading

CVE-2019-18276 is a restricted shell escape in bash where attempting to enable a non-existent builtin triggers implicit dynamic loading of a shared object file, bypassing the security checks that prevent explicit dynamic loading in restricted mode. This allows an attacker to execute arbitrary code by placing a malicious .so file in the current directory or BASH_LOADABLES_PATH and then using the enable command with a non-existent builtin name.