CVE-2026-39888: Python Exec Unrestricted Builtins Sandboxcve-2026-39888-python-exec-unrestricted-builtins-sandbox
A globals mapping is being constructed with '__builtins__' aliased to the unrestricted real __builtins__. When this mapping is passed to exec()/eval() for untrusted code, it provides NO sandboxing: the executed code can call exec/eval/compile/__import__/open directly, and can also escape via frame-traversal (e.__traceback__.tb_frame.f_back.f_builtins["exec"]
