Converting between :class:`int` and :class:`str` in bases other than 2 (binary), 4, 8 (octal), 16 (hexadecimal), or 32 such as base 10 (decimal) now raises a :exc:`ValueError` if the number of digits in string form is above a limit to avoid potential denial of service attacks due to the algorithmic complexity. This is a mitigation for CVE-2020-10735.

This new limit can be configured or disabled by environment variable, command line flag, or :mod:`sys` APIs. See the :ref:`integer string conversion length limitation <int_max_str_digits>` documentation. The default limit is 4300 digits in string form.

Patch by Gregory P. Smith [Google] and Christian Heimes [Red Hat] with feedback from Victor Stinner, Thomas Wouters, Steve Dower, Ned Deily, and Mark Dickinson.