setuptools: MANIFEST.in exclusion bypass in sdist via Unicode normalization collision (NFC/NFD) on macOS APFS/HFS+ (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 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.
AI Analysis
Technical Summary
The vulnerability CVE-2026-59890 exists in setuptools, a Python package management tool. The FileList component responsible for file exclusions does not properly normalize Unicode file names when applying exclusion rules. On macOS APFS or HFS+ file systems, a specially crafted file name using a different Unicode normalization form (NFD) can bypass an intended exclusion rule (NFC). This results in sensitive files that should have been excluded being included in source distributions, leading to potential information disclosure. Red Hat has issued a fix in the miniforge3 package version 26.3.2.3-r0 and related RPMs, including python-setuptools 83.0.0-4.hum1. The CVSS v3.1 base score assigned by Red Hat is 6.1 (medium severity), with a local attack vector, low complexity, no privileges required, user interaction required, and high confidentiality impact.
Potential Impact
The vulnerability can cause sensitive files that should be excluded from source distributions to be included due to Unicode normalization bypass. This leads to potential information disclosure. The integrity and availability impacts are low or none. The attack requires local access and user interaction, with low complexity and no privileges required.
Mitigation Recommendations
A security update is available and should be applied. Red Hat has released fixed versions of the affected packages, including python-setuptools 83.0.0-4.hum1 and related RPMs in miniforge3 version 26.3.2.3-r0. Users should upgrade to these fixed versions to remediate the vulnerability. No other mitigations meeting Red Hat's criteria are currently available.
setuptools: MANIFEST.in exclusion bypass in sdist via Unicode normalization collision (NFC/NFD) on macOS APFS/HFS+ (CVE-2026-59890)
Description
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.
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-59890 exists in setuptools, a Python package management tool. The FileList component responsible for file exclusions does not properly normalize Unicode file names when applying exclusion rules. On macOS APFS or HFS+ file systems, a specially crafted file name using a different Unicode normalization form (NFD) can bypass an intended exclusion rule (NFC). This results in sensitive files that should have been excluded being included in source distributions, leading to potential information disclosure. Red Hat has issued a fix in the miniforge3 package version 26.3.2.3-r0 and related RPMs, including python-setuptools 83.0.0-4.hum1. The CVSS v3.1 base score assigned by Red Hat is 6.1 (medium severity), with a local attack vector, low complexity, no privileges required, user interaction required, and high confidentiality impact.
Potential Impact
The vulnerability can cause sensitive files that should be excluded from source distributions to be included due to Unicode normalization bypass. This leads to potential information disclosure. The integrity and availability impacts are low or none. The attack requires local access and user interaction, with low complexity and no privileges required.
Mitigation Recommendations
A security update is available and should be applied. Red Hat has released fixed versions of the affected packages, including python-setuptools 83.0.0-4.hum1 and related RPMs in miniforge3 version 26.3.2.3-r0. Users should upgrade to these fixed versions to remediate the vulnerability. No other mitigations meeting Red Hat's criteria are currently available.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:37530
- Cve Count
- 1
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a5c47772a4a8d5989eb4fe8
Added to database: 07/19/2026, 03:41:43 UTC
Last enriched: 08/15/2026, 00:25:53 UTC
Last updated: 09/14/2026, 10:01:32 UTC
Views: 69
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