Vulnerability in 9router (CVE-2026-56681)
Summary
Vulnerability in 9router (CVE-2026-56681). Risk of unauthorized operations or information disclosure. Exploitable via GET /api/v1/models. Mitigation: upgrade to 0.5.8 or later.
Original description
The description as published by the source.
Summary
9router determines whether an incoming request originates from localhost by trusting the X-9r-Real-Ip HTTP request header. This header is intended to be produced and sanitized exclusively by the bundled custom-server.js layer from the TCP socket address. In deployment modes where requests reach Next.js directly (the header is never stripped/regenerated), a remote, unauthenticated attacker can simply send X-9r-Real-Ip: 127.0.0.1 and be treated as a local client. This bypasses the API-key requirement on the public LLM API (/api/v1/*), granting unauthenticated access to the instance owner's configured provider resources.
Affected Component
- src/dashboardGuard.js
- isLocalRequest() — trusts the client-supplied X-9r-Real-Ip header to decide loopback origin
- canAccessPublicLlmApi() — grants access to /api/v1/* when isLocalRequest() returns true, skipping API-key validation
- Verified affected route: GET /api/v1/models
- Product version tested: 9router-app 0.5.4 (Next.js 16.2.9)
Root Cause
The authorization layer makes a security decision based on a client-controllable HTTP header. isLocalRequest() reads X-9r-Real-Ip and, if its value is a loopback address (127.0.0.1), classifies the request as local. The design assumes this header can only be set by the trusted custom-server.js wrapper (which derives it from the unspoofable socket address and strips any inbound copy). When the application is served without that wrapper, Next.js passes the attacker-sup…
Source: NIST National Vulnerability Database 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-2026-56681 has been found in 9router.
Attackers can target a specific entry point like GET /api/v1/models over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 7.3/10.
What to do: upgrade 9router to 0.5.8 or later.
If unsure, ask your IT team or search "9router CVE-2026-56681" on the vendor's site.
CVE-2026-56681 (9router) — CWE-807 / CVSS v3 7.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: GET /api/v1/models
Patched: 0.5.8 — 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-807) exists in 9router. Attackers reach the vulnerable code path via GET /api/v1/models without authentication.
Check the vendor advisory for the affected versions of 9router. Attack surface: GET /api/v1/models.
Severity: High (CVSS 7.3/10). Risk of unauthorized operations or information disclosure.
Update to 0.5.8.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual GET /api/v1/models requests with malformed payloads or SQL meta-characters. Run grep -r '9router' . 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 '9router' . | 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
9router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 'GET /api/v1/models' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
GET /api/v1/models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 9router to 0.5.8ステージング環境で 0.5.8 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 GET /api/v1/models 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
- web github.com
- web github.com
- web github.com
- web github.com