Command Injection in libpython (CVE-2026-4786)
Summary
Command injection in libpython (CVE-2026-4786). Confidential information can be exposed externally. Mitigation: upgrade to 3.14.5 or later.
Original description
The description as published by the source.
Mitgation of CVE-2026-4519 was incomplete. If the URL contained "%action" the mitigation could be bypassed for certain browser types the "webbrowser.open()" API could have commands injected into the underlying shell. See CVE-2026-4519 for details.
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
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-2026-4786 has been found in libpython.
Confidential information can be exposed externally. CVSS score: 7.1/10.
What to do: upgrade libpython to 3.14.5 or later.
If unsure, ask your IT team or search "libpython CVE-2026-4786" on the vendor's site.
CVE-2026-4786 (libpython) — CWE-77 / CVSS v3 7.1
Attack vector: remote (network-reachable) / unauthenticated
Patched: 3.14.5 — 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-77) exists in libpython.
Check the vendor advisory for the affected versions of libpython.
Severity: High (CVSS 7.1/10). Confidential information can be exposed externally.
Update to 3.14.5.
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 'libpython' . 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
-
1Identify exposure identify
grep -r 'libpython' . | 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
libpython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 libpython to 3.14.5ステージング環境で 3.14.5 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
- Debian DEBIAN-CVE-2026-4786 pypy3 Fixed in: 7.3.22+dfsg-1
- Ubuntu UBUNTU-CVE-2026-4786 python2.7
References
- advisory mail.python.org
- patch github.com
- patch github.com
- patch github.com
- patch github.com
- patch github.com
- patch github.com
- report github.com
- web github.com
- web nvd.nist.gov
- web mail.python.org
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web bugzilla.redhat.com
- web security.access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web access.redhat.com
- web github.com
- web access.redhat.com