CVE-2026-59890Public exploit

Source-distribution file disclosure via unnormalized exclusions

Published Jul 8, 2026 · Updated Jul 8, 2026

Unicode comparison flaws in setuptools before 83.0.0 allow attackers to disclose excluded files through macOS-built source distributions. FileList compares compiled MANIFEST.in exclusion globs with on-disk names byte for byte, without normalizing NFC and NFD forms. The bypass requires an NFD-named file on APFS or HFS+ and a user-built source distribution; publishing it can irreversibly expose the excluded file.

CVSS severity6.1
Medium
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Unicode comparison flaws in setuptools before 83.0.0 allow attackers to disclose excluded files through macOS-built source distributions. FileList compares compiled MANIFEST.in exclusion globs with on-disk names byte for byte, without normalizing NFC and NFD forms. The bypass requires an NFD-named file on APFS or HFS+ and a user-built source distribution; publishing it can irreversibly expose the excluded file.

The record

CVE
CVE-2026-59890
Published
Jul 8, 2026
Updated
Jul 8, 2026
Vendor
Python Packaging Authority
Product
setuptools
Classifications
CWE-176, CWE-697
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 8, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 83.0.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Python Packaging Authority · setuptoolsversion=< 83.0.0

Published CVSS scores

6.1GitHub, Inc.CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-176Improper Handling of Unicode Encoding
CWE-697Incorrect Comparison

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo