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CVE-2026-4270
medium
CVSS 5.5
Vulnerability in Amazon awslabs-aws-api-mcp-server (CVE-2026-4270)
Summary
vulnerability in Amazon awslabs-aws-api-mcp-server (CVE-2026-4270). Confidential information can be exposed externally. Mitigation: upgrade to `1.3.9` or later.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **CVE-2026-4270** has been found in Amazon awslabs-aws-api-mcp-server.
Confidential information can be exposed externally. CVSS score: 5.5/10.
What to do: upgrade Amazon awslabs-aws-api-mcp-server to **1.3.9** or later.
If unsure, ask your IT team or search "Amazon awslabs-aws-api-mcp-server CVE-2026-4270" on the vendor's site.
CVE-2026-4270 (Amazon awslabs-aws-api-mcp-server) — CWE-424 / CVSS v3 5.5
Attack vector: local / unauthenticated
Patched: `1.3.9` — 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.
❓ What is the problem
**A vulnerability** (CWE-424) exists in Amazon awslabs-aws-api-mcp-server.
📍 Affected scope
Amazon awslabs-aws-api-mcp-server — .
🔥 Severity
Severity: Medium (CVSS 5.5/10). Confidential information can be exposed externally
🔧 How to fix
Update to **1.3.9**.
🛡️ Workaround
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
🔍 Detection
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run `grep -r 'awslabs-aws-api-mcp-server' .` 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
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1Identify exposure identify
grep -r 'awslabs-aws-api-mcp-server' . | 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 `awslabs-aws-api-mcp-server` を grep し、稼働しているサービス・バージョンを把握する。
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6Apply patch patch
Upgrade awslabs-aws-api-mcp-server to 1.3.9ステージング環境で 1.3.9 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と、Step 3 で見つけた異常検知の続報チェックを含めること。
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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。
Affected packages
PyPI
awslabs-aws-api-mcp-server
[{"type":"ECOSYSTEM","events":[{"introduced":"0.2.14"},{"fixed":"1.3.9"}]}]
pip
awslabs.aws-api-mcp-server
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.9"}]}]
pip
awslabs-aws-api-mcp-server
[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.3.9"}]}]
References
- advisory https://aws.amazon.com/security/security-bulletins/2026-007-AWS/
- advisory https://pypi.org/project/awslabs.aws-api-mcp-server/1.3.9/
- advisory https://nvd.nist.gov/vuln/detail/CVE-2026-4270
- advisory https://github.com/advisories/GHSA-2cpp-j2fc-qhp7
- AWS https://aws.amazon.com/security/security-bulletins/rss/2026-007-aws/
- package https://github.com/awslabs/mcp
- web https://github.com/awslabs/mcp/security/advisories/GHSA-2cpp-j2fc-qhp7
- web https://aws.amazon.com/security/security-bulletins/2026-007-AWS
- web https://pypi.org/project/awslabs.aws-api-mcp-server/1.3.9
- web https://github.com/pypa/advisory-database/tree/main/vulns/awslabs-aws-api-mcp-server/PYSEC-2026-162.yaml