BaaS Breach Simulator

Multi-Tenant Ledger Isolation & Sandbox Escape Test Harness for Banking-as-a-Service

baas-breach-simulator is an institutional-grade, zero-external-dependency adversary emulation test harness designed for sponsor banks, Banking-as-a-Service (BaaS) platforms, and core banking architects. It mathematically proves multi-tenant ledger isolation, simulating deterministic "sandbox escapes" across shared For-Benefit-Of (FBO) omnibus accounts to prevent ledger drift crises (e.g. Synapse/Evolve Bank failure modes) before FDIC and OCC regulatory examinations.

                  [ Sponsor Bank Custody Reserve: $1,000,000.00 ]
                                         │
                                         ▼
            ┌────────────────────────────────────────────────────────┐
            │        Pooled For-Benefit-Of (FBO) Omnibus Account     │
            ├────────────────────────────┬───────────────────────────┤
            │  Program Tenant A ($500k)  │  Program Tenant B ($300k) │
            └──────────────┬─────────────┴─────────────┬─────────────┘
                           │                           │
                           ▼                           ▼
            ┌────────────────────────────────────────────────────────┐
            │         BaaS Adversary Emulation Breach Vectors        │
            ├────────────────────────────────────────────────────────┤
            │ 1. Sub-Millisecond Asynchronous Race Overdraft         │
            │ 2. Cross-Tenant Parameter ID Spoofing                  │
            │ 3. Single-Key Maker-Checker Dual-Custody Bypass        │
            │ 4. Unbacked Ledger Credit Inflation (Phantom Balance)  │
            │ 5. Orphan Settlement Two-Phase Commit Drift            │
            └───────────────────────────┬────────────────────────────┘
                                        │
                                        ▼
            ┌────────────────────────────────────────────────────────┐
            │         Mathematical Balance Conservation Invariant    │
            │          Δ = Reserve - ∑ Tenants ≡ 0 (No Drift)        │
            └───────────────────────────┬────────────────────────────┘
                                        │
                                        ▼
             [ Automated FDIC Schedule RC-E Conformance Report ]
             [ Chained SHA-256 Telemetry Stream (a2zsoc.com) ]

---

🏛️ Regulatory Context & The Synapse Crisis

In traditional BaaS architectures, a chartered sponsor bank maintains a single omnibus FBO account at the Federal Reserve. The BaaS middleware or FinTech program maintains a virtual shadow ledger tracking individual consumer balances.

When platforms lack hardware-grade mathematical ledger isolation:

1. Asynchronous Race Overdrafts: Concurrent API debits allow FinTech Program A to overdraft into negative balances, implicitly consuming the customer deposits of FinTech Program B.
2. Orphan Settlement Drift: Failure during two-phase commits leaves external payment rails (FedNow/ACH) executed while internal core ledgers roll back, causing millions in unaccounted drift.
3. Regulatory Action: The FDIC, Federal Reserve, and OCC have issued cease-and-desist consent orders mandating real-time proof that sponsor banks can reconcile every dollar down to individual beneficial owners (FDIC Call Report Schedule RC-E).

---

📐 Mathematical Invariant Formulation

1. The Fundamental Balance Conservation Invariant

At all points in time $t$, the physical custody reserve held at the central bank must strictly equal the sum of all tenant ledger partitions:

$$\Delta(t) = \mathcal{R}_{\text{custody}}(t) - \sum_{i=1}^N \mathcal{B}_i(t) \equiv 0$$

Where:

• $\mathcal{R}_{\text{custody}}$ is the real-time cash balance in the central bank FBO master account.
• $\mathcal{B}_i$ is the allocated ledger balance of FinTech Program Tenant $i$.
• If $\Delta(t) < 0$, phantom credit inflation has occurred.
• If $\Delta(t) > 0$, unreconciled settlement leakage has occurred.

2. Multi-Tenant Isolation Condition

For any transaction $\mathcal{T}_k$ initiated by Tenant $A$ attempting to transfer amount $x$:

$$\mathcal{B}_A(t^+) = \mathcal{B}_A(t) - x \ge 0 \quad \land \quad \forall j \neq A, ; \mathcal{B}_j(t^+) = \mathcal{B}_j(t)$$

If $\mathcal{B}_A(t^+) < 0$ or any $\mathcal{B}_j(t^+) \neq \mathcal{B}_j(t)$, a Multi-Tenant Sandbox Escape has occurred.

---

⚡ Adversary Emulation Flow

sequenceDiagram
    autonumber
    actor RedTeam as Bank Risk / Purple Team
    participant Simulator as BaaSBreachSimulator
    participant Auditor as LedgerIsolationAuditor
    participant FBO as Sandboxed Omnibus FBO
    participant Invariant as Invariant Conservation Checker
    participant SOC as a2zsoc Evidence Vault

    RedTeam->>Simulator: run_full_isolation_audit(FBO, AttackSuite)
    loop For Each Attack Vector
        Simulator->>Auditor: execute_simulation(AttackIntent)
        Auditor->>FBO: Mutate Balance (Race, Spoof, Bypass)
        FBO-->>Auditor: Resulting Tenant States
        Auditor->>Invariant: compute_drift_cents()
        Invariant-->>Auditor: Drift Δ & Overdraft Flags
        Auditor-->>Simulator: SimulationResult (Contained vs Escape)
    end
    Simulator->>SOC: Chained SHA-256 Audit Hash Emitted
    SOC-->>Simulator: Hash Recorded
    Simulator-->>RedTeam: BaaSIsolationReport (Grade: A+ or F_FAILED)

Loading

---

⚡ Performance Benchmark

Benchmarked on Apple Silicon (M-series) using pure Python standard library:

Metric	Measured Value	Standard Required
Isolation Verification Latency	21.29 µs / simulation	$< 100\text{ ms}$
Simulation Throughput	46,969 sims / sec	$> 1,000\text{ sims / sec}$
External Dependencies	0 (Zero)	Standard Library
Audit Hash Overhead	$< 2 \text{ µs}$	N/A

---

🚀 Quickstart & Usage

1. Installation

git clone https://github.com/AAH20/baas-breach-simulator.git
cd baas-breach-simulator

2. Test Hardened Multi-Tenant Ledger (Passes FDIC RC-E)

python3 -m projects.baas_breach_simulator.cli test-hardened

Output:

=====================================================================================
🏦 BAAS BREACH SIMULATOR - RUNNING ADVERSARY EMULATION [HARDENED (ATOMIC ISOLATION)]
=====================================================================================
Sponsor Bank:              Pacific Horizon Bancorp
Report Identifier:         RPT-BAAS-541ada63a9d5
Isolation Grade:           A+
FDIC Schedule RC-E:        ✅ COMPLIANT
Escapes Prevented:         4 / 4
Escapes Detected (Breach): 0 / 4
Audit Chained Hash:        11272b06bae15d43b4b273d0e1739a21...
-------------------------------------------------------------------------------------
SIMULATION OUTCOMES:
  [🛡️ CONTAINED] Vector: ASYNC_RACE_OVERDRAFT       | Severity: CONTAINED
  [🛡️ CONTAINED] Vector: TENANT_ID_SPOOFING         | Severity: CONTAINED
  [🛡️ CONTAINED] Vector: MAKER_CHECKER_BYPASS       | Severity: CONTAINED
  [🛡️ CONTAINED] Vector: UNBACKED_CREDIT_INFLATION  | Severity: CONTAINED
=====================================================================================

3. Test Vulnerable Naive Ledger (Simulates Synapse/Evolve Collapse)

python3 -m projects.baas_breach_simulator.cli test-vulnerable

Output:

=====================================================================================
🏦 BAAS BREACH SIMULATOR - RUNNING ADVERSARY EMULATION [VULNERABLE (NAIVE LEDGER)]
=====================================================================================
Sponsor Bank:              Pacific Horizon Bancorp
Report Identifier:         RPT-BAAS-541ada63a9d5
Isolation Grade:           F_FAILED
FDIC Schedule RC-E:        ❌ NON-COMPLIANT / REJECTED
Escapes Prevented:         0 / 4
Escapes Detected (Breach): 4 / 4
Audit Chained Hash:        07733023579089b3bb85844a4391836b...
-------------------------------------------------------------------------------------
SIMULATION OUTCOMES:
  [🚨 ESCAPE] Vector: ASYNC_RACE_OVERDRAFT       | Severity: CRITICAL
  [🚨 ESCAPE] Vector: TENANT_ID_SPOOFING         | Severity: CRITICAL
  [🚨 ESCAPE] Vector: MAKER_CHECKER_BYPASS       | Severity: HIGH
  [🚨 ESCAPE] Vector: UNBACKED_CREDIT_INFLATION  | Severity: CRITICAL
=====================================================================================

4. Run High-Throughput Invariant Benchmark

python3 -m projects.baas_breach_simulator.cli benchmark --iterations 5000

---

💻 Python Programmatic API

from baas_breach_simulator import (
    A2ZSocBaaSBridge,
    OmnibusFboAccount,
    ProgramTenant,
    SimulationAttackIntent,
    BreachVectorType,
)

# 1. Initialize the institutional bridge
bridge = A2ZSocBaaSBridge()

# 2. Configure FBO custody reserve and tenant partitions
fbo = OmnibusFboAccount(
    fbo_id="FBO-CENTRAL-01",
    sponsor_bank_name="First Regional BaaS Bank",
    total_custody_reserve_cents=50000000,  # $500k
    tenants={
        "T-NEO": ProgramTenant("T-NEO", "NeoBank App", 30000000, 30000000),
        "T-WAGE": ProgramTenant("T-WAGE", "Earned Wage Provider", 20000000, 20000000),
    }
)

# 3. Formulate breach attack intents
suite = [
    SimulationAttackIntent(
        attack_id="ATK-RACE",
        vector=BreachVectorType.ASYNC_RACE_OVERDRAFT,
        source_tenant_id="T-NEO",
        attempted_amount_cents=20000000,
        concurrency_workers=3,
    )
]

# 4. Execute audit
report = bridge.run_full_isolation_audit(fbo, suite, enforce_strict_locks=True)

print(f"Grade:          {report.overall_isolation_grade}")
print(f"FDIC RC-E:      {report.fdic_schedule_rce_compliant}")
print(f"Audit Hash:     {report.audit_hash}")

---

🧪 Testing

Execute the test suite with 100% standard library coverage:

python3 -m unittest discover -s projects/baas_breach_simulator/tests

---

📜 License

Apache License 2.0. See LICENSE for details.