CVE-2026-59890 — Improper Handling of Unicode Encoding

Vendor	Product	Version range	Fixed in
pypa	setuptools	< 83.0.0	83.0.0
python	setuptools	< 83.0.0	83.0.0
python	setuptools	>= 0 < 83.0.0	83.0.0

Red Hat

setuptools: setuptools: MANIFEST.in exclusion bypass in sdist via Unicode normalization collision (NFC/NFD)

vendor_redhat·2026-07-08·CVSS 6.1

CVE-2026-59890 [MEDIUM] CWE-1025 setuptools: setuptools: MANIFEST.in exclusion bypass in sdist via Unicode normalization collision (NFC/NFD) setuptools: setuptools: MANIFEST.in exclusion bypass in sdist via Unicode normalization collision (NFC/NFD) setuptools is a package that allows users to download, build, install, upgrade, and uninstall Python packages. Prior to 83.0.0, FileList applied MANIFEST.in exclude, global-exclude, recursive-exclude, and prune directives by matching compiled glob patterns against on-disk file names without Unicode normalization, so on macOS APFS or HFS+ an NFD file name could bypass an NFC exclusion rule and be packed into a source distribution. This issue is fixed in version 83.0.0. 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 ove

GHSA

setuptools: MANIFEST.in exclusion bypass in sdist via Unicode normalization collision (NFC/NFD) on macOS APFS/HFS+

ghsa·2026-07-21

CVE-2026-59890 [MEDIUM] CWE-176 setuptools: MANIFEST.in exclusion bypass in sdist via Unicode normalization collision (NFC/NFD) on macOS APFS/HFS+ setuptools: MANIFEST.in exclusion bypass in sdist via Unicode normalization collision (NFC/NFD) on macOS APFS/HFS+ ## Summary When building a source distribution (`python -m build --sdist` / `setup.py sdist`), setuptools' `FileList` applies `MANIFEST.in` directives (`exclude`, `global-exclude`, `recursive-exclude`, `prune`) by matching a compiled glob against on-disk file names **byte-for-byte, with no Unicode normalization**. On normalization-preserving filesystems (notably macOS APFS and HFS+), a file written in NFD and a `MANIFEST.in` rule written in NFC refer to the same file but are byte-distinct, so the exclusion silently fails to match. A file the maintainer intended to exclude is then packed into the `.tar.gz` and, if published, uploaded to the public, immutable PyPI index. ## D

VulDB

pypa setuptools up to 82.x FileList MANIFEST.in unicode encoding

vuldb·2026-07-13·CVSS 6.1

CVE-2026-59890 [MEDIUM] pypa setuptools up to 82.x FileList MANIFEST.in unicode encoding A vulnerability has been found in pypa setuptools up to 82.x and classified as problematic. Affected is an unknown function of the file MANIFEST.in of the component FileList. The manipulation leads to improper handling of unicode encoding. This vulnerability is referenced as CVE-2026-59890. The attack can only be performed from a local environment. No exploit is available.

CVE-2026-59890: setuptools is a package that allows users to download, build, install, upgrade, and uninstall Python packages. Prior to 83.0.0, FileList applied MANIFEST.in…

Affected

CVSS provenance