CVE-2022-45061

An issue was discovered in Python before 3.11.1. An unnecessary quadratic
algorithm exists in one path when processing some inputs to the IDNA (RFC
3490) decoder, such that a crafted, unreasonably long name being presented
to the decoder could lead to a CPU denial of service. Hostnames are often
supplied by remote servers that could be controlled by a malicious actor;
in such a scenario, they could trigger excessive CPU consumption on the
client attempting to make use of an attacker-supplied supposed hostname.
For example, the attack payload could be placed in the Location header of
an HTTP response with status code 302. A fix is planned in 3.11.1, 3.10.9,
3.9.16, 3.8.16, and 3.7.16.

Bugs

• <https://github.com/python/cpython/issues/98433&gt;