CVE-2026-59890

A flaw was found in setuptools, a Python package management tool. The FileList component, responsible for handling file exclusions, did not properly normalize Unicode file names when applying exclusion rules. This oversight could allow a specially crafted file name, using a different Unicode normalization form (NFD) on macOS APFS or HFS+ file systems, to bypass an intended exclusion rule (NFC). As a result, sensitive files that should have been excluded could be inadvertently included in a source distribution, leading to information disclosure.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.