Microservices Architectures
Service mesh trust, API gateway placement, inter-service authentication (mTLS, service tokens), east-west traffic policy, secret distribution and sidecar security boundaries.
Security Architecture Review
Find the structural risks. Before attackers do.
A design-level review of trust boundaries, authentication architecture, data flow patterns, encryption design and inter-service communication. We catch structural flaws in your architecture before code ships and before they become expensive production vulnerabilities.
- 0
- STRIDE categories
- 0%
- Trust boundaries mapped
- 0
- Threat model outputs
- 0
- Architecture review report
Trust Boundary
Client
API Gateway
Missing TLS 1.3
Auth Service
No token rotation
App Service
Database
Unencrypted at rest
External API
No egress filtering
Trust boundaries: 3
Threats identified: 7
Critical design gaps: 2
Aligned to the frameworks your security teams rely on
STRIDE
DREAD
NIST SP 800-53
OWASP SAMM
ISO 27001
TOGAF
// What's Included
What's Included in Our Security Architecture Review
A security architecture review examines the structural decisions behind your system: how components communicate, where trust is placed, how data moves across boundaries, and whether the controls in place actually match the threats your design faces. We apply formal threat modeling, map every data flow and trust boundary, identify control gaps, and deliver concrete design-level recommendations.
// Scope
Architecture Types We Review
Our security architecture review covers any system design that handles sensitive data, enforces access control, or operates across trust boundaries. These are the architecture patterns we review most frequently.
Event-Driven & Message Queue Systems
Message broker access controls, event schema validation, poison message handling, consumer authorization, dead-letter queue exposure and event replay attack surface.
Multi-Tenant SaaS Platforms
Tenant isolation models (row-level, schema-level, instance-level), cross-tenant data leakage paths, shared infrastructure blast radius, tenant-scoped key management and audit logging.
Data Pipelines & ETL
Data classification enforcement across pipeline stages, encryption in transit between transformations, PII masking and tokenization placement, lineage tracking and access control at the storage layer.
Identity & Access Architectures
IdP federation trust, token lifecycle management, session binding and revocation, RBAC/ABAC model completeness, privilege escalation paths and step-up authentication design.
Cloud-Native & Serverless Designs
Function-level IAM over-permissioning, cold-start secret injection, API gateway authorization gaps, shared-resource side-channel risks and ephemeral compute trust assumptions.
// Risk Areas
Common Architecture-Level Risk Areas We Identify
Across enterprise systems, the same categories of design-level risk appear repeatedly. These are the structural weaknesses our security architecture review targets, each one a class of flaw that is far cheaper to resolve at the design stage than after deployment.
Area 01 / 06
Trust Boundary Violations
Trust Boundary Violations
Trust boundaries define where one security context ends and another begins: internal network versus public internet, one microservice versus another, one tenant's data versus another's. The most common design flaw we find is implicit trust across these boundaries, where an internal API accepts requests from a public-facing gateway without re-validating identity or authorization, or where inter-service calls carry no authentication at all because "it's all internal." These gaps become the primary path for lateral movement once any single component is compromised.
Common pattern
An API gateway authenticates external requests but internal services behind it communicate over plain HTTP with no service-to-service authentication, treating network-level isolation as a substitute for identity verification.
Authentication & Identity Design Flaws
Authentication design flaws go beyond weak passwords. We look at the structural decisions: how tokens are issued, scoped and rotated; whether session binding prevents token replay across devices; how federated identity trust is established and validated; and whether step-up authentication is required for sensitive operations. A common finding is that the primary login flow is well-designed but secondary flows (API key generation, service account provisioning, machine-to-machine tokens) bypass the same controls entirely.
Common pattern
User-facing authentication uses short-lived JWTs with proper rotation, but service accounts use long-lived API keys with no expiry, no rotation schedule and overly broad scopes that persist even after the responsible team changes.
Data Protection & Encryption Gaps
Encryption is rarely all-or-nothing. Most systems encrypt data in transit (TLS) and often at rest at the storage level, but gaps appear in the middle: temporary files written in plaintext during processing, PII cached in unencrypted Redis instances, sensitive fields logged before masking is applied, or backups stored without the same encryption as the primary data store. We map the full data lifecycle and identify every point where sensitive data exists outside encryption coverage.
Common pattern
The primary database uses transparent data encryption, but an analytics pipeline extracts PII into a data warehouse where encryption at rest is not enabled, and ETL staging tables hold plaintext copies of sensitive fields.
Insufficient Logging & Audit Design
Security monitoring only works when every security-relevant event is captured with sufficient detail to reconstruct what happened. Architectures frequently log application errors but miss security events: failed authentication attempts, authorization denials, privilege changes, data exports, administrative actions, and configuration changes. Without these, incident response teams have no forensic trail and compliance auditors have no evidence of control effectiveness. We assess what is logged, where it is stored, whether it is tamper-proof, and whether retention meets regulatory requirements.
Common pattern
Application logs capture HTTP errors and performance metrics but do not record authorization decisions, and audit logs for administrative actions exist only in the identity provider with no forwarding to the SIEM.
Inter-Service Communication Risks
In distributed architectures, the security of inter-service communication determines whether a single compromised service leads to a full breach. We evaluate whether east-west traffic uses mutual TLS, whether service identities are properly scoped, whether message queues enforce producer/consumer authorization, and whether circuit breakers and rate limiters protect against denial-of-service propagation. A recurring finding is that services trust message content from other internal services without validation, allowing a compromised upstream service to inject malicious payloads.
Common pattern
Microservices communicate over an internal network with no mutual TLS and no per-service authorization policy, relying entirely on network segmentation that does not exist in the Kubernetes cluster's flat network.
Third-Party Integration Exposure
Every external integration introduces a trust dependency. We review how third-party API credentials are stored and rotated, whether OAuth scopes are minimized, how webhook endpoints validate sender identity, and what happens to your system's availability and data integrity if a third-party service is compromised or goes offline. The blast radius of a third-party breach depends entirely on the architectural choices made at integration time: shared credentials, over-broad permissions, and missing input validation on incoming webhook data are the most common findings.
Common pattern
A single API key with full read/write access is shared across multiple third-party integrations, stored in environment variables with no rotation policy, and the same key is used in both production and staging environments.
0+
Avg. control gaps identified per review
0
Risk domains assessed per engagement
0%
Threat model coverage (STRIDE)
5
Deliverables per engagement
// Methodology
How Our Security Architecture Review Works
Every security architecture review follows five phases over four weeks. Each phase produces a tangible output your engineering and security teams keep.
architecture-review.sh
#!/bin/bash -- architecture-review
$ collect --diagrams --docs --interviews
→ Architecture docs ingested. 8 stakeholders interviewed.
✓ Documentation baseline established -- Week 1
$ model-threats --stride --data-flows
→ STRIDE applied. 3 trust boundaries. 14 data flows mapped.
✓ Threat model constructed -- Week 1-2
$ map-boundaries --internal --external --third-party
→ Trust boundary violations: 4. Elevation paths: 2.
✓ Boundary mapping complete -- Week 2-3
$ analyze-gaps --controls --encryption --logging
→ 7 control gaps. 3 critical design recommendations.
✓ Risk register compiled -- Week 3-4
$ report --threat-model --recommendations --walkthrough
→ Threat model delivered. Architecture fixes prioritized.
✓ Engagement complete -- Week 4
$
01
Collect
Week 1
Architecture Documentation & Stakeholder Interviews
We collect and review all available architecture documentation: system diagrams, data flow diagrams, API specifications, infrastructure-as-code, network topology and existing security documentation. Where documentation is incomplete, we conduct interviews with architects and engineers to build the baseline understanding. Documentation gaps are themselves flagged as findings.
02
Model
Week 1-2
Threat Model Construction (STRIDE)
Using STRIDE categories, we systematically enumerate threats against each component and interaction in the architecture. Each threat is scored using DREAD to establish relative priority. The result is a formal threat model document that your team can maintain and update as the architecture evolves.
03
Map
Week 2-3
Data Flow & Trust Boundary Mapping
We trace every path that sensitive data takes through the system, identify every trust boundary crossing, and verify that appropriate controls (authentication, authorization, encryption, validation) exist at each crossing point. Missing or implicit trust assumptions are documented as control gaps with elevation path analysis.
04
Analyze
Week 3-4
Control Gap Analysis & Risk Rating
Each identified threat is compared against the controls currently in place. We rate gaps by likelihood and impact, producing a prioritized risk register. Controls that exist but are insufficient (wrong layer, wrong granularity, misconfigured) are documented separately from controls that are entirely absent. Encryption, logging and access control gaps are called out individually.
05
Deliver
Week 4
Recommendations Report & Walkthrough
We deliver a comprehensive report containing the threat model, data flow maps, control gap matrix and prioritized recommendations mapped to NIST SP 800-53 and ISO 27001 control families. A live walkthrough session with your architecture and security teams ensures every finding is understood and an implementation plan is agreed.
// Deliverables
What You Receive From Our Security Architecture Review
Every security architecture review concludes with a set of deliverables designed for three audiences: architects making design decisions, engineers implementing fixes, and leadership prioritizing investment.
01
Threat Model Document
A formal STRIDE-based threat model covering every component, data flow and trust boundary in scope, with DREAD scoring for each identified threat. Designed to be maintained as a living document by your team.
02
Data Flow & Trust Boundary Maps
Visual diagrams showing how sensitive data traverses system components, every trust boundary crossing, and where controls are present, insufficient or absent at each transition point.
03
Control Gap Matrix
A structured matrix mapping each threat to existing controls, rating gap severity by likelihood and impact, and referencing the corresponding NIST SP 800-53 and ISO 27001 control families.
04
Prioritized Recommendations Report
Specific, implementable design recommendations for every control gap, prioritized by risk reduction and implementation effort, written for architects and engineers implementing the changes.
05
Live Walkthrough Session
A working session with your architecture and security teams to walk through every finding, answer questions, discuss trade-offs and agree on an implementation roadmap.
Five deliverables. One review. A structural security baseline your team can build on.
Schedule your review// Why CipherTrivia
Why Choose CipherTrivia for Security Architecture Review
Architecture reviews require deep systems thinking, not just checklist compliance. Here is what sets our approach apart.
Architects Reviewing Architects
Reviews are conducted by senior engineers with hands-on experience building and securing distributed systems, not by generalist auditors following a checklist. We understand the trade-offs because we have made them ourselves.
Formal Threat Modeling, Not Generic Checklists
We build a STRIDE threat model specific to your architecture. Every finding traces directly to a threat scenario against your system, not a generic best-practice recommendation copied from a framework document.
Actionable Recommendations
Every finding includes a specific, implementable recommendation at the design level: which control to add, at which layer, with what configuration. No vague "improve security posture" statements.
Compliance-Mapped Output
Findings and recommendations are mapped to NIST SP 800-53 control families and ISO 27001 Annex A controls, providing direct evidence for compliance audits without additional rework.
// Proof of Work
A Security Architecture Review Case Study
Architecture Review · SaaS Platform
Identifying Trust Boundary Gaps in a Multi-Tenant SaaS Platform
A B2B SaaS provider preparing for SOC 2 Type II engaged us to review the security architecture of their multi-tenant platform. We identified 14 control gaps including cross-tenant data leakage paths through shared caching layers, missing encryption at rest on analytics staging tables, and service-to-service calls with no authentication. All findings were remediated before the compliance audit.
View all case studies// FAQ
Frequently Asked Questions About Security Architecture Review
What is a security architecture review?
A security architecture review is a design-level assessment of your system's structure, data flows, trust boundaries and security controls. Unlike penetration testing, which targets running code, an architecture review examines how components interact, where trust is assumed, and whether the controls in place match the threats the system actually faces. The output is a prioritized set of structural risks and actionable recommendations to address them before they become exploitable vulnerabilities.
How does a security architecture review differ from a penetration test?
A penetration test targets a running application to find exploitable vulnerabilities in code and configuration. A security architecture review operates earlier in the lifecycle: it examines the design itself, including data flow diagrams, trust boundaries, authentication and authorization models, encryption schemes and inter-service communication patterns. The goal is to identify structural weaknesses that would be expensive or disruptive to fix after deployment. Ideally both are performed: architecture review during design, penetration testing after deployment.
When should we schedule a security architecture review?
The highest-value timing is during the design phase of a new system or ahead of a significant architectural change such as migrating to microservices, adopting a new identity provider, adding multi-tenancy, or moving workloads to a new cloud region. Reviews are also valuable before compliance audits (ISO 27001, SOC 2) as they surface control gaps that auditors would flag. Some teams schedule reviews annually as part of their security program.
What documentation do we need to provide?
At minimum we need architecture diagrams (even informal ones), a description of major components and their responsibilities, data flow documentation showing how sensitive data moves through the system, and details of your authentication and authorization model. If available, infrastructure-as-code templates, API specifications, network topology diagrams and existing threat models accelerate the review. We can work with incomplete documentation and will flag gaps as findings.
How long does a security architecture review take?
A focused review of a single service or bounded context typically takes one to two weeks. A full enterprise architecture review covering multiple systems, identity infrastructure and data pipelines runs two to four weeks depending on complexity and documentation readiness. We agree on scope and timeline during an initial scoping call so there are no surprises.
Get Started With a Security Architecture Review
Tell us about your system architecture and we will scope a security architecture review engagement that fits your timeline, compliance requirements and risk priorities.