sdist · setuptools: MANIFEST.in exclusion bypass
Affects python@3.11Source GCVE Database
Not known to be exploited · CVSS 6.1 Medium : upgrade to 3.11.15_4 when convenient.
Data as of 26 Oct 2026, 19:42 UTC
- Patch
- Available – fixed in 3.11.15_4
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 8 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade python@3.11 to 3.11.15_4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewpython@3.11pkg:brew/python%403.11Other threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available in setuptools version 3.11.15_4 that normalizes both the walked file paths and MANIFEST.in patterns to a canonical Unicode form before matching, preventing exclusion bypass. Users should upgrade to this fixed version or later. Until patched, maintainers should be aware that MANIFEST.in exclusions are normalization-insensitive on macOS and consider erring on the side of excluding more files. No other immediate action is required.
Description
A Unicode normalization mismatch in setuptools' handling of MANIFEST.in exclusions can cause files intended to be excluded from source distributions to be included instead on macOS APFS/HFS+ filesystems. This occurs because setuptools matches file names byte-for-byte without Unicode normalization, leading to exclusion bypass when file names differ only in Unicode normalization form (NFC vs NFD). This can result in unintended disclosure of files containing secrets or private data when publishing to PyPI.
References
- github.com/pypa/setuptools/security/advisories/GHSA-h35f-9h28-mq5c (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-59890 (opens in a new tab)
- github.com/pypa/setuptools/commit/dd9f436a36486b4cb8a4c70a2321548b0be09b8f (opens in a new tab)
- github.com/pypa/advisory-database/tree/main/vulns/setuptools/PYSEC-2026-3447.yaml (opens in a new tab)
- github.com/pypa/setuptools (opens in a new tab)
- github.com/pypa/setuptools/releases/tag/v83.0.0 (opens in a new tab)