A flaw was found in the tempfile.TemporaryDirectory class in python3/cpython3. The class may dereference symbolic links during permission-related errors, resulting in users that run privileged programs being able to modify permissions of files referenced by the symbolic link.

A flaw was found in the Python/CPython 'zipfile' that can allow a zip-bomb type of attack. An attacker may craft a zip file format, leading to a Denial of Service when processed.

A vulnerability was identified in the kjd/idna library, specifically within the `idna.encode()` function, affecting version 3.6. The issue arises from the function's handling of crafted input strings, which can lead to quadratic complexity and consequently, a denial of service condition. This vulnerability is triggered by a crafted input that causes the `idna.encode()` function to process the input with considerable computational load, significantly increasing the processing time in a quadratic manner relative to the input size.