Vulnerability in setuptools (CVE-2026-59890)
Summary
Vulnerability in setuptools (CVE-2026-59890). Confidential information can be exposed externally. Mitigation: upgrade to 83.0.0 or later.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-59890 has been found in setuptools.
Confidential information can be exposed externally. CVSS score: 6.1/10.
What to do: upgrade setuptools to 83.0.0 or later.
If unsure, ask your IT team or search "setuptools CVE-2026-59890" on the vendor's site.
CVE-2026-59890 (setuptools) — CWE-176 / CVSS v3 6.1
Attack vector: local / unauthenticated
Patched: 83.0.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-176) exists in setuptools.
Check the vendor advisory for the affected versions of setuptools.
Severity: Medium (CVSS 6.1/10). Confidential information can be exposed externally.
Update to 83.0.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'setuptools' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'setuptools' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
setuptoolsを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade setuptools to 83.0.0ステージング環境で 83.0.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-59890 py3-setuptools Fixed in: 83.0.0-r0
- Ubuntu UBUNTU-CVE-2026-59890 setuptools
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- patch github.com
- web github.com
- web github.com
- web github.com