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CVE-2026-40190
medium
CVSS 5.6
Vulnerability in langchain (CVE-2026-40190)
Summary
vulnerability in langchain (CVE-2026-40190). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to `0.5.18` or later.
AI summary snake-internal / snake-material-v2
A vulnerability tracked as **CVE-2026-40190** has been found in langchain.
Risk of unauthorized operations or information disclosure. CVSS score: 5.6/10.
What to do: upgrade langchain to **0.5.18** or later.
If unsure, ask your IT team or search "langchain CVE-2026-40190" on the vendor's site.
CVE-2026-40190 (langchain) — CWE-1321 / CVSS v3 5.6
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: `0.5.18` — 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-1321) exists in langchain.
📍 Affected scope
langchain — .
🔥 Severity
Severity: Medium (CVSS 5.6/10). Risk of unauthorized operations or information disclosure
🔧 How to fix
Update to **0.5.18**.
🛡️ 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 'langchain' .` 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 'langchain' . | 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 `langchain` 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 langchain to 0.5.18ステージング環境で 0.5.18 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。
References
- exploit [email protected]