March 4, 2026
10:42 p.m.
There is a MEDIUM severity vulnerability affecting CPython.
The import hook in CPython that handles legacy *.pyc files (SourcelessFileLoader) is incorrectly handled in FileLoader (a base class) and so does not use io.open_code() to read the .pyc files. sys.audit handlers for this audit event therefore do not fire.
Please see the linked CVE ID for the latest information on affected versions: