python -m http.server no longer allows terminal control characters sent
within a garbage request to be printed to the stderr server log.
This is done by changing the :mod:`http.server`
:class:`BaseHTTPRequestHandler` .log_message method to replace control
characters with a \xHH hex escape before printing.
Avoid publishing list of active per-interpreter audit hooks via the :mod:`gc` module
The IDNA codec decoder used on DNS hostnames by :mod:`socket` or
:mod:`asyncio` related name resolution functions no longer involves a
quadratic algorithm. This prevents a potential CPU denial of service if an
out-of-spec excessive length hostname involving bidirectional characters
were decoded. Some protocols such as :mod:`urllib` http 3xx redirects
potentially allow for an attacker to supply such a name.
Update bundled libexpat to 2.5.0
Port XKCP's fix for the buffer overflows in SHA-3 (CVE-2022-37454).
On Linux the :mod:`multiprocessing` module returns to using filesystem backed unix domain sockets for communication with the forkserver process instead of the Linux abstract socket namespace. Only code that chooses to use the :ref:`"forkserver" start method <multiprocessing-start-methods>` is affected.
Abstract sockets have no permissions and could allow any user on the system in the same network namespace (often the whole system) to inject code into the multiprocessing forkserver process. This was a potential privilege escalation. Filesystem based socket permissions restrict this to the forkserver process user as was the default in Python 3.8 and earlier.
This prevents Linux CVE-2022-42919.
The deprecated mailcap module now refuses to inject unsafe text (filenames, MIME types, parameters) into shell commands. Instead of using such text, it will warn and act as if a match was not found (or for test commands, as if the test failed).