GraphQL Security Testing

GraphQL Security Testing

The GraphQL security testing module is a dedicated scanner for GraphQL APIs. It discovers GraphQL endpoints across the attack surface, tests each for exposed introspection, extracts and hashes the schema, flags sensitive fields, and optionally runs the external graphql-cop Docker container for 12 additional misconfiguration checks.

It runs as GROUP 6 Phase A — in parallel with Nuclei — because both scanners consume the same inputs (BaseURL, Endpoint, Technology) and produce Vulnerability nodes, but have zero data dependency on each other. Disabled by default. Enable in the project settings under the GraphQL Security tab.

---

Why a dedicated GraphQL scanner

Generic web scanners miss GraphQL-specific weaknesses because they depend on the schema being visible and because GraphQL collapses the REST surface onto a single URL with POST bodies:

• Introspection exposure — schema leak that maps every query, mutation, and subscription, plus sensitive field names
• Schema-only DoS — alias overloading, batch query, directive overloading, circular introspection
• IDE exposure — GraphiQL / GraphQL Playground / Apollo Studio accessible in production
• CSRF via non-POST methods — queries/mutations accepted via GET or url-encoded POST
• Field suggestion leakage — "Did you mean..." replies that bypass introspection-off defences
• Trace mode — Apollo tracing extension exposes query timings and resolver names

The module combines a native introspection/sensitive-field test (PR #93, Phase 1) with the external graphql-cop scanner (Phase 2) that runs 12 targeted checks per endpoint.

---

Pipeline position

GROUP 5  → Resource enumeration (Katana, Hakrawler, jsluice, FFuf, GAU, Kiterunner, Arjun)
GROUP 5b → JS Reconnaissance
GROUP 6 Phase A  → Nuclei  ||  GraphQL Security Testing     ← parallel fan-out
GROUP 6 Phase B  → MITRE enrichment (consumes Nuclei CVEs)

Phase A is fanned out via ThreadPoolExecutor, and each scanner uses an _isolated wrapper that deep-copies the shared combined_result so the two threads never race on the same dict.

---

Endpoint discovery

Before testing, the scanner builds a candidate list of GraphQL endpoints from five sources and deduplicates them:

Source	Extraction Logic
User-specified	Comma-separated URLs from the GRAPHQL_ENDPOINTS setting
HTTP probe	Endpoints with application/graphql in the Content-Type header
Resource enumeration	Katana/Hakrawler/FFuf/GAU/Kiterunner endpoints whose path contains graphql, gql, or query (POST only). Also any endpoint with query, mutation, variables, or operationName as a parameter
JS Reconnaissance	Findings typed as graphql or graphql_introspection in the JS Recon output
Pattern probing	Common GraphQL paths appended to every discovered base URL

Pattern probing — primary patterns (tried on every base URL):

/graphql    /api/graphql    /v1/graphql    /v2/graphql

Secondary patterns (tried only on base URLs that already showed GraphQL evidence):

/query         /api/query
/gql           /api/gql
/graphiql      /api/graphiql
/playground    /api/playground

All discovered endpoints then pass through Rules of Engagement filtering (ROE_EXCLUDED_HOSTS with *.example.com wildcard support) before any probe fires. Skipped endpoints are counted in endpoints_skipped.

---

Introspection test

For each in-scope endpoint, the scanner runs a 3-step probe sequence:

1. Reachability probe — POST { __typename } with configurable auth headers. Non-200 responses short-circuit and mark the endpoint as non-GraphQL
2. Simple introspection — POST { __schema { queryType { name } mutationType { name } } }. If this succeeds with data.__schema present, introspection is enabled
3. Deep introspection — Full introspection query with a configurable TypeRef recursion depth (1-20). If the response exceeds 10 MB, the scanner falls back to the simple result to avoid memory pressure

Why TypeRef depth matters: GraphQL type references are singly-linked chains (e.g. NON_NULL → LIST → NON_NULL → NAMED). A fixed 3-level fragment truncates info on deeply-wrapped types — GRAPHQL_DEPTH_LIMIT lets the scanner match the actual wrapping depth of the target schema. Default is 10, which covers nearly all real-world schemas; the hard ceiling is 20 to avoid server-side query-depth rejection.

Schema extraction output:

Per endpoint, the scanner computes and stores:

• introspection_enabled / schema_extracted — booleans
• queries_count, mutations_count, subscriptions_count
• operations.{queries,mutations,subscriptions} — name lists
• schema_hash — 16-char SHA256 prefix (for change detection across scans)
• List of sensitive fields matching: password, secret, token, key, api, private, credential, auth, ssn, credit, card, payment, bank, account, pin, cvv, salary, medical

The introspection finding severity is dynamic:

Condition	Severity
Introspection enabled (baseline)	info
More than 0 mutations found	info + mutation count appended
More than 20 mutations found	medium
Sensitive fields detected	medium

---

graphql-cop external scanner (Phase 2)

When GRAPHQL_COP_ENABLED is on, the scanner launches the dolevf/graphql-cop:1.14 Docker container per endpoint for 12 additional checks. The container runs as Docker-in-Docker — the recon container needs access to /var/run/docker.sock.

Command shape:

docker run --rm [--network host]  dolevf/graphql-cop:1.14 \
       -t <endpoint> -o json [-f] [-d] \
       [-H '{"Authorization":"Bearer ..."}'] [-T] [-x <proxy>]

Network mode: defaults to the Docker bridge network. When USE_TOR_FOR_RECON is on at the project level, the container is launched with --network host and passed -T to route all probes through Tor. A global HTTP_PROXY is forwarded via -x.

The 12 tests

Test Key (graphql-cop)	Title	Severity	Mapped Vulnerability Type	DoS?
field_suggestions	Field Suggestions	info	graphql_field_suggestions_enabled	—
introspection	Introspection	high	graphql_introspection_enabled	—
detect_graphiql	GraphQL IDE	medium	graphql_ide_exposed	—
get_method_support	GET Method Query Support	medium	graphql_get_method_allowed	—
alias_overloading	Alias Overloading	low	graphql_alias_overloading	✓
batch_query	Array-based Query Batching	low	graphql_batch_query_allowed	✓
trace_mode	Trace Mode	info	graphql_tracing_enabled	—
directive_overloading	Directive Overloading	low	graphql_directive_overloading	✓
circular_query_introspection	Introspection-based Circular Query	low	graphql_circular_introspection	✓
get_based_mutation	Mutation is allowed over GET	high	graphql_get_based_mutation	—
post_based_csrf	POST based url-encoded query	medium	graphql_post_csrf	—
unhandled_error_detection	Unhandled Errors Detection	info	graphql_unhandled_error	—

The introspection test is disabled by default — the native introspection test above already covers it without spawning a container. Everything else runs by default.

DoS note: Stealth mode forces the four DoS tests (alias, batch, directive, circular) off. Because the 1.14 image on DockerHub does not honor the -e exclusion flag (it was added in v1.15 main but not yet released), the scanner still executes those probes and then filters the findings Python-side. For true zero-traffic suppression, use the master Enable graphql-cop toggle.

Endpoint capability flags

graphql-cop always records five capability flags on the GraphQL Endpoint node — even when the test returned negative — so the graph captures server state explicitly (e.g. "GraphiQL exposed: false" is stored, not just absent):

Flag	Source Test	Meaning
graphql_graphiql_exposed	detect_graphiql	IDE page served at the endpoint
graphql_tracing_enabled	trace_mode	Apollo tracing extension returns timing data
graphql_get_allowed	get_method_support	Endpoint accepts GET queries
graphql_field_suggestions_enabled	field_suggestions	"Did you mean..." responses enabled
graphql_batching_enabled	batch_query	Server responds to array-batched requests

A graphql_cop_ran = true flag is also set after the container exits, regardless of individual test results.

---

Authentication

The scanner attaches auth headers to every request (native introspection + graphql-cop). Five auth types are supported, all configured via three settings:

Setting	Values
GRAPHQL_AUTH_TYPE	bearer / cookie / header / basic / apikey
GRAPHQL_AUTH_VALUE	Token / cookie string / raw header value / user:pass pair (basic)
GRAPHQL_AUTH_HEADER	Custom header name (used with header or apikey)

Auth type behavior:

Type	Emitted Header
bearer	Authorization: Bearer <value>
cookie	Cookie: <value>
basic	Authorization: Basic <base64(user:pass)>
header	<GRAPHQL_AUTH_HEADER or X-Auth-Token>: <value>
apikey	<GRAPHQL_AUTH_HEADER or X-API-Key>: <value>

All auth values are masked in logs — long values show xxxx...yyyy, short values show xx***, basic auth shows username:***.

---

Full parameter reference

Core

Parameter	Default	Clamp	Description
GRAPHQL_SECURITY_ENABLED	false	—	Master toggle
GRAPHQL_INTROSPECTION_TEST	true	—	Run the native introspection probe
GRAPHQL_TIMEOUT	30	1-600	Request timeout in seconds
GRAPHQL_RATE_LIMIT	10	0-100	Global max requests per second (0 = unlimited)
GRAPHQL_CONCURRENCY	5	1-20	Parallel endpoint-testing threads
GRAPHQL_DEPTH_LIMIT	10	1-20	TypeRef fragment recursion depth
GRAPHQL_RETRY_COUNT	3	0-10	Retry attempts for 429/5xx and network errors
GRAPHQL_RETRY_BACKOFF	2.0	0-10	urllib3 backoff_factor (exponential)
GRAPHQL_VERIFY_SSL	true	—	Verify TLS certificates
GRAPHQL_ENDPOINTS	""	—	Comma-separated custom endpoint URLs

Authentication

Parameter	Default	Description
GRAPHQL_AUTH_TYPE	""	bearer / cookie / header / basic / apikey
GRAPHQL_AUTH_VALUE	""	Token, cookie, value, or user:pass
GRAPHQL_AUTH_HEADER	""	Custom header name for header / apikey modes

graphql-cop

Parameter	Default	Description
GRAPHQL_COP_ENABLED	false	Master toggle for the external scanner
GRAPHQL_COP_DOCKER_IMAGE	dolevf/graphql-cop:1.14	Docker image (pinned to 1.14 for stable -e behaviour)
GRAPHQL_COP_TIMEOUT	120	Per-endpoint container timeout in seconds
GRAPHQL_COP_FORCE_SCAN	false	Pass -f to override the built-in GraphQL detector
GRAPHQL_COP_DEBUG	false	Pass -d to emit X-GraphQL-Cop-Test header per request

graphql-cop per-test toggles

Parameter	Default	DoS?
GRAPHQL_COP_TEST_FIELD_SUGGESTIONS	true	—
GRAPHQL_COP_TEST_INTROSPECTION	false	—
GRAPHQL_COP_TEST_GRAPHIQL	true	—
GRAPHQL_COP_TEST_GET_METHOD	true	—
GRAPHQL_COP_TEST_ALIAS_OVERLOADING	true	✓
GRAPHQL_COP_TEST_BATCH_QUERY	true	✓
GRAPHQL_COP_TEST_TRACE_MODE	true	—
GRAPHQL_COP_TEST_DIRECTIVE_OVERLOADING	true	✓
GRAPHQL_COP_TEST_CIRCULAR_INTROSPECTION	true	✓
GRAPHQL_COP_TEST_GET_MUTATION	true	—
GRAPHQL_COP_TEST_POST_CSRF	true	—
GRAPHQL_COP_TEST_UNHANDLED_ERROR	true	—

Stealth mode forces the four DoS tests off.

---

Output structure

Results are stored under combined_result.graphql_scan:

{
  "summary": {
    "endpoints_discovered": 12,
    "endpoints_tested": 9,
    "endpoints_skipped": 3,
    "introspection_enabled": 2,
    "vulnerabilities_found": 7,
    "by_severity": {
      "critical": 0, "high": 1, "medium": 3, "low": 2, "info": 1
    }
  },
  "discovered_endpoints": ["https://api.example.com/graphql", "..."],
  "endpoints": {
    "https://api.example.com/graphql": {
      "tested": true,
      "introspection_enabled": true,
      "schema_extracted": true,
      "queries_count": 34,
      "mutations_count": 12,
      "subscriptions_count": 2,
      "schema_hash": "9d2e4b1a...",
      "operations": {"queries": [...], "mutations": [...], "subscriptions": [...]},
      "graphql_cop_ran": true,
      "graphql_graphiql_exposed": true,
      "graphql_tracing_enabled": false,
      "graphql_get_allowed": true,
      "graphql_field_suggestions_enabled": true,
      "graphql_batching_enabled": false,
      "error": null
    }
  },
  "vulnerabilities": [ /* normalized finding dicts */ ]
}

---

Graph schema

Consumes: BaseURL, Endpoint, Domain, Technology

Produces: Vulnerability, CVE

Enriches: Endpoint — adds the capability flags, schema hash, operation counts, introspection booleans, and error state listed above.

Ingestion is gated by a schema contract in graph_db/mixins/graphql_mixin.py — KNOWN_VULN_KEYS and KNOWN_ENDPOINT_INFO_KEYS define every field the scanner can emit. If a scanner adds a new key without updating the mixin, an ingest-time warning fires so the change doesn't silently drop data.

---

Rules of Engagement

Discovered endpoints are filtered by ROE_EXCLUDED_HOSTS before testing. Wildcards are supported: *.staging.example.com matches both staging.example.com and any of its subdomains. Filtered endpoints are counted under summary.endpoints_skipped for visibility.

---

Stealth mode

When stealth mode is enabled on the project:

Setting	Stealth Override
GRAPHQL_RATE_LIMIT	2
GRAPHQL_CONCURRENCY	1 (sequential)
GRAPHQL_TIMEOUT	60
GRAPHQL_COP_TEST_ALIAS_OVERLOADING	false
GRAPHQL_COP_TEST_BATCH_QUERY	false
GRAPHQL_COP_TEST_DIRECTIVE_OVERLOADING	false
GRAPHQL_COP_TEST_CIRCULAR_INTROSPECTION	false

Other GraphQL settings (GRAPHQL_SECURITY_ENABLED, GRAPHQL_INTROSPECTION_TEST) stay unchanged — passive introspection probing is still valuable in stealth mode.

---

Partial recon

GraphQL scanning is available as a Partial Recon tool. The modal accepts custom URLs that must be within the project scope — they are injected via the GRAPHQL_ENDPOINTS setting and expanded by the same discovery pipeline used in the full recon run.

• GRAPHQL_SECURITY_ENABLED is force-set to true for the partial run (overrides the project toggle)
• settings_overrides from the modal bypass the stored project settings for that run
• Graph targets are pulled from existing BaseURL, Endpoint, and JS Recon findings — toggleable via the "Include existing graph targets" checkbox

See Recon Pipeline Workflow — Partial Recon for the modal layout.

---

Related pages

• Project Settings Reference — GraphQL Security Testing — full parameter tables
• Recon Pipeline Workflow — pipeline diagram showing GraphQL in the Vuln Scanning stage
• Running Reconnaissance — execution model
• Rules of Engagement — host exclusion rules applied before probes fire