postura 0.1.1

Attack Surface Posture Agent — agentic security graph for your codebase

POSTURA

Agentic Attack Surface Posture Intelligence

POSTURA is an agentic security system that maintains a persistent Neo4j threat graph of your codebase, updating incrementally on every commit. Unlike static analysis tools that examine code in isolation, POSTURA reasons about compositional risk — vulnerability chains that emerge from how endpoints, functions, data stores, and dependencies interact at runtime.

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Why POSTURA

Static tools (Bandit, Semgrep) find individual vulnerabilities but miss the context:

What static tools miss	How POSTURA closes the gap
Missing auth (CWE-306) — no static test for "should have auth"	Auth graph edge absence + public endpoint flag
Contextual severity — code severity ≠ runtime severity	Graph paths: exposure × datastore sensitivity
Supply-chain CVE reachability — CVE known, call-path unknown	USES edges: Function→Dependency + endpoint reachability
SQLi + PII chains — B608 finds SQLi, but not the PII path	CHAINS_TO: Finding→DataStore(PII=true)
Dependency blast radius — not modeled anywhere	Graph traversal: Dependency→Function→Endpoint

On the included vulnerable Flask fixture, Bandit detects 4/6 findings (67%), all at incorrect severities, and 0/3 vulnerability chains. POSTURA targets 6/6 findings and 3/3 chains.

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Architecture

GitHub webhook
     │
     ▼
WebhookReceiver (FastAPI)
     │  push / PR event
     ▼
ScopeAnalyzer ──► git diff → changed files
     │
     ▼
AST Parser (tree-sitter)
  ├─ ASTNode (functions, classes)
  ├─ CallEdge (function→function)
  ├─ DataAccessEvent (SQL/ORM reads)
  └─ ImportedPackages (top-level)
     │
     ▼
GraphBuilder / GraphUpdater (Neo4j)
  Nodes: Finding · Endpoint · Function · DataStore · Dependency · TrustZone
  Edges: HANDLED_BY · CALLS · AFFECTS · CHAINS_TO · USES · READS_FROM · IN_ZONE
     │
     ▼
Reasoning Layer (LangGraph ReAct agent + 6 tools)
  ├─ graph_query        — read-only Cypher
  ├─ knowledge_retrieve — BM25 + ChromaDB hybrid search (CWE/CVE/OWASP)
  ├─ trace_dataflow     — endpoint → function → datastore paths
  ├─ find_chains        — vulnerability chain discovery
  ├─ assess_exploitability — context-aware severity scoring
  └─ generate_remediation  — LLM-powered fix suggestions
     │
     ▼
Delivery Layer
  ├─ GitHub PR comment (POST /repos/.../issues/.../comments)
  ├─ GitHub commit status (POST /repos/.../statuses/...)
  └─ Posture history (PostureSnapshot nodes in Neo4j)
     │
     ▼
REST API (FastAPI)
  /api/v1/posture      /api/v1/findings   /api/v1/chains
  /api/v1/endpoints    /api/v1/dashboard  /api/v1/history
  /api/v1/trend        /api/v1/query      /api/v1/knowledge/*

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Quickstart

Prerequisites

• Docker (for Neo4j and Redis)
• Python 3.11+

1. Start infrastructure

docker run -d --name neo4j \
  -e NEO4J_AUTH=neo4j/postura_dev \
  -p 7474:7474 -p 7687:7687 \
  neo4j:5

docker run -d --name redis -p 6379:6379 redis:7-alpine

2. Install POSTURA

python3.11 -m venv .venv
source .venv/bin/activate
pip install -e ".[dev]" --no-cache-dir

3. Configure

cp .env.example .env
# Edit .env:
# POSTURA_NEO4J_URI=bolt://localhost:7687
# POSTURA_NEO4J_USER=neo4j
# POSTURA_NEO4J_PASSWORD=postura_dev
# POSTURA_ANTHROPIC_API_KEY=sk-ant-...
# POSTURA_GITHUB_TOKEN=ghp_...   (for PR comments)

4. Bootstrap knowledge base

# OWASP Top 10 (offline, always works)
curl -X POST "http://localhost:8000/api/v1/knowledge/reload?sources=owasp"

# CWE + CVE (requires network — downloads MITRE XML and NVD API)
curl -X POST "http://localhost:8000/api/v1/knowledge/reload?sources=cwe,cve"

5. Ingest a repository

# Start the API server
uvicorn postura.api.app:app --reload

# Start Celery worker (optional — for async analysis)
celery -A postura.tasks.celery_app worker --loglevel=info

# Point your GitHub repo's webhook at:
# http://<your-server>/webhook/github
# Content-Type: application/json
# Secret: $POSTURA_WEBHOOK_SECRET

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REST API

Method	Endpoint	Description
GET	/api/v1/posture	Current posture score + finding counts
GET	/api/v1/findings	All findings (filter by status, severity)
GET	/api/v1/findings/{uid}	Finding detail with graph context
GET	/api/v1/findings/{uid}/chains	Chains involving a finding
POST	/api/v1/findings/{uid}/remediate	LLM remediation suggestion
GET	/api/v1/endpoints	All endpoints with trust zone / auth
GET	/api/v1/chains	All vulnerability chains
GET	/api/v1/dashboard	Top risks, trend, chain count
GET	/api/v1/history	Time-series posture history
GET	/api/v1/trend	Posture trend over N snapshots
POST	/api/v1/query	Natural language graph query
GET	/api/v1/diff/{sha}	Findings introduced/resolved by commit
GET	/api/v1/dependencies/{name}/blast-radius	Dependency blast radius
POST	/api/v1/knowledge/reload	Reload CWE/CVE/OWASP knowledge
GET	/api/v1/knowledge/status	Knowledge collection sizes
GET	/api/v1/knowledge/search	Hybrid search across knowledge base

Natural language query

curl -X POST http://localhost:8000/api/v1/query \
  -H "Content-Type: application/json" \
  -d '{"question": "Which public endpoints have no authentication?"}'

{
  "question": "Which public endpoints have no authentication?",
  "answer": "There are 2 public unauthenticated endpoints: GET /admin/users and GET /fetch. The /admin/users endpoint exposes PII from the users table without any authentication check (CWE-306).",
  "cypher": "MATCH (e:Endpoint {is_public: true, auth_required: false}) RETURN e.path, e.method",
  "result_count": 2,
  "raw_results": [...]
}

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Evaluation

# Static baseline only (no Neo4j required)
PYTHONPATH=. python evaluation/baseline_static.py

# Full comparison report (requires ingested graph)
PYTHONPATH=. python evaluation/report.py

# Save Markdown report
PYTHONPATH=. python evaluation/report.py --output evaluation/REPORT.md

Benchmark results on vulnerable Flask fixture (tests/fixtures/vulnerable_flask_app):

Metric	Bandit	POSTURA
Findings detected (6 total)	4 (67%)	6 (100%)
Severity correct	❌ 3/4 underrated	✅ Contextual
Chains detected (3 total)	0 (0%)	3 (100%)
Missing auth (F2/CWE-306)	❌	✅
Supply-chain reachability	❌	✅

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Development

# Run all tests (skips e2e that need Docker)
PYTHONPATH=. .venv/bin/pytest tests/ -v

# Run evaluation tests only
PYTHONPATH=. .venv/bin/pytest tests/test_evaluation/ -v

# Type check
.venv/bin/mypy src/postura --ignore-missing-imports

# Lint
.venv/bin/ruff check src/

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Phase Completion

Phase	Description	Status
P1	Foundation (models, ingest, AST parser)	✅
P2	Threat Graph (Neo4j builder, chain discovery, severity scoring)	✅
P3	Incremental Updates (webhook, git diff, updater)	✅
P4	Reasoning Layer (LangGraph agent, knowledge base, 6 tools)	✅
P5	Delivery & Reporting (GitHub integration, dashboard, NL query)	✅
P5.5	Evaluation Framework (ground truth, baseline, report generator)	✅

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License

MIT