← Back
CVE-2026-42047
high
CVSS 8.6
Information Disclosure in express (CVE-2026-42047)
Summary
vulnerability in express (CVE-2026-42047). Confidential information can be exposed externally.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **CVE-2026-42047** has been found in express.
Confidential information can be exposed externally. CVSS score: 8.6/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "express CVE-2026-42047" on the vendor's site.
CVE-2026-42047 (express) — CWE-200 / CVSS v3 8.6
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Workaround: restrict the serve() endpoint at the framework or reverse-proxy layer to accept only GET, POST, and PUT.
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.
❓ What is the problem
**information disclosure** (CWE-200) exists in express.
📍 Affected scope
express — .
🔥 Severity
Severity: High (CVSS 8.6/10). Confidential information can be exposed externally
🔧 How to fix
Update to the patched release per vendor advisory.
🛡️ Workaround
Workaround: restrict the serve() endpoint at the framework or reverse-proxy layer to accept only GET, POST, and PUT.
🔍 Detection
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run `grep -r 'express' .` against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response Actions (7 steps)
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'express' . | 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 `express` を grep し、稼働しているサービス・バージョンを把握する。
-
5Apply temporary workaround mitigate
restrict the serve() endpoint at the framework or reverse-proxy layer to accept only GET, POST, and PUT.パッチが適用されるまでの応急処置として、restrict the serve() endpoint at the framework or reverse-proxy layer to accept only GET, POST, and PUT. を実施。回避策の副作用 (機能低下) を確認した上で。
-
7Post-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 Step 3 と同じログクエリでアラート再発が無いか継続監視。
References
- web [email protected]
- web [email protected]