SSRF (Server-Side Request Forgery) in n8n (CVE-2026-56348)
Summary
SSRF in n8n (CVE-2026-56348). Confidential information can be exposed externally. Exploitable via POST /rest/dynamic-node-parameters/options. Mitigation: upgrade to 2.20.0 or later.
Original description
The description as published by the source.
n8n before 2.20.0 contains a credential exfiltration vulnerability in the POST /rest/dynamic-node-parameters/options endpoint that allows authenticated users to bypass Allowed HTTP Request Domains restrictions. Attackers with credential access can cause the n8n server to issue HTTP requests with credentials to unauthorized hosts, exfiltrating sensitive authentication data.
Source: GitHub Security Advisories (Global) 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-2026-56348 has been found in n8n.
Attackers can target a specific entry point like POST /rest/dynamic-node-parameters/options over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 9.1/10.
What to do: upgrade n8n to 2.20.0 or later.
If unsure, ask your IT team or search "n8n CVE-2026-56348" on the vendor's site.
CVE-2026-56348 (n8n) — CWE-918 / CVSS v3 9.1
Attack vector: remote (network-reachable) / no user interaction
Attack surface: POST /rest/dynamic-node-parameters/options
Patched: 2.20.0 — 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.
SSRF (CWE-918) exists in n8n. Attackers reach the vulnerable code path via POST /rest/dynamic-node-parameters/options.
Check the vendor advisory for the affected versions of n8n. Attack surface: POST /rest/dynamic-node-parameters/options.
Severity: Critical (CVSS 9.1/10). Confidential information can be exposed externally.
Update to 2.20.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /rest/dynamic-node-parameters/options requests with malformed payloads or SQL meta-characters. Run grep -r 'n8n' . 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 'n8n' . | 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
n8nを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'POST /rest/dynamic-node-parameters/options' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /rest/dynamic-node-parameters/optionsへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade n8n to 2.20.0ステージング環境で 2.20.0 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と、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against POST /rest/dynamic-node-parameters/options on staging to confirm patch closes the vector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 2 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
References
- advisory github.com
- advisory vulncheck.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- web github.com