Modern Attack Surfaces¶
Walk the lifecycle › Development A: Technical feasibility › Going deeper
The lifecycle in this framework applies to any environment. The assumptions that most detection programs carry do not. Many were formed when the estate consisted of Windows endpoints on a corporate network, and they transfer poorly to environments where the endpoint is not the point of compromise.
This deep dive belongs to the technical feasibility phase because the first question it changes is what can be observed. Each section describes, for one kind of environment, which assumptions no longer hold, where the most valuable detection opportunities lie, and what that means for applying the framework.
Running example. The consent phishing detection is an identity detection. It involves no endpoint and no malware, and the attacker's access survives a password reset. The identity section below explains why this pattern has become common.
The environments covered are identity, the cloud control plane, SaaS applications, containers and Kubernetes, CI/CD and the software supply chain, operational technology, and AI and machine learning systems.
Identity¶
Identity is the primary attack surface. In most intrusions that matter, no malware executes and no endpoint is compromised.
What changes¶
| Assumption | Reality |
|---|---|
| Compromise begins at an endpoint | Compromise begins at an identity provider, frequently from an unmanaged device |
| Authentication is the control point | Post-authentication authorization is the control point; tokens and consent grants outlive credentials |
| Password reset contains the incident | Password reset does nothing to a stolen refresh token, a consented application, or an added authentication method |
| MFA is a detection boundary | MFA fatigue, adversary-in-the-middle proxies and device-code phishing all produce successful, MFA-satisfied sign-ins |
Priority detection surfaces¶
| Surface | Why |
|---|---|
| OAuth consent and permission grants | Persistent delegated access that survives credential rotation. See the worked example |
| Authentication method registration | Adding a method is the quietest persistence mechanism in most tenants |
| Conditional access policy modification | Disabling a control is a precondition to using it |
| Privileged role assignment and eligible-role activation | Privilege escalation in a cloud directory |
| Token anomalies | Impossible travel is weak; token replay from a new device or unexpected client ID is strong |
| Federation and trust changes | Adding a federated domain or signing certificate is total tenant compromise |
| Service principal credential addition | A new secret on an existing application is backdoor persistence with legitimate-looking telemetry |
Framework implications¶
- Asset criticality in the planning rubric applies to identities, not only systems. A privileged identity is a tier 1 asset.
- Response playbooks MUST include token revocation explicitly. Consent removal or password reset alone does not end access, and this step is the one most often omitted.
- Robustness: identity telemetry is comparatively stable and schema-consistent, so behavioral detections here tend to last longer than endpoint equivalents.
Cloud control plane¶
What changes¶
The control plane is an API. Compromise is a sequence of authorized API calls, each individually legitimate. There is no malicious binary to find.
| Assumption | Reality |
|---|---|
| Lateral movement is network-based | Lateral movement is role assumption and cross-account trust |
| Persistence is a file or service | Persistence is an IAM role, a Lambda trigger, an automation account or a resource policy |
| Exfiltration crosses the perimeter | Exfiltration is a bucket policy change or a snapshot shared to an external account |
| The blast radius is the host | The blast radius is whatever the compromised principal may call |
Priority detection surfaces¶
| Surface | Why |
|---|---|
| IAM policy and role changes | Privilege escalation, and the precondition to nearly everything else |
| Resource sharing to external accounts | Snapshot, image and bucket sharing is quiet, complete exfiltration |
| Logging and guardrail modification | Disabling CloudTrail, audit logs or a security service precedes the rest |
| Credential and key creation | New access keys on an existing principal |
| Serverless function and automation changes | Execution-on-trigger persistence |
| Unusual regions | Activity in never-used regions is a durable, high-precision signal |
Framework implications¶
- Telemetry is cheap and complete relative to endpoint.
TEL-3inventory work is comparatively easy here; the difficulty is volume and cost. - Many control-plane detections are
invarianttier: the API call is the technique. This is the highest-yield robustness territory available. - Preventive controls (service control policies, guardrails) are strong here,
which changes the
coverage_gapscore. Monitor the guardrail itself.
SaaS¶
The estate most programs monitor least. Data lives in applications the security team does not administer and frequently cannot query.
| Surface | Why |
|---|---|
| Third-party application integration | The most common SaaS-to-SaaS lateral path |
| Sharing and permission changes | Public link creation, external collaborator addition |
| Administrative action outside change windows | Small admin populations make anomalies visible |
| Bulk export and download | The clearest exfiltration signal available in most SaaS platforms |
| Authentication bypass | Legacy protocols, app passwords, and API tokens that skip conditional access |
The dominant constraint is telemetry availability. Many SaaS platforms emit
audit logs only at premium licence tiers or with short retention. Make this a
procurement requirement: audit log availability, retention and API access
belong in the security requirements for any SaaS purchase. Raising it after
signature is raising it too late, and FEA-1 will otherwise block the use case
permanently.
Containers and Kubernetes¶
| Surface | Why |
|---|---|
| Workload spawning an interactive shell | Containers are normally single-purpose; a shell is anomalous by construction |
| Privileged or host-namespace containers | The standard escape path |
| Service account token abuse | Kubernetes credentials are files in the filesystem |
| API server anomalies | exec, port-forward, secret enumeration |
| Unexpected image sources | Registry outside the approved set |
| Runtime drift from the image | A process running that was not in the image |
The advantage here is that container environments are more predictable than
general-purpose hosts. Immutability makes deviation detectable. Detections built
on "this workload should never do X" are often invariant tier and exceptionally
precise.
The disadvantage is ephemerality: a container may live for seconds. Telemetry must be streamed and correlated by workload identity, not host.
CI/CD and software supply chain¶
The highest-leverage target in most organizations, and the least monitored. Build systems hold production credentials, run arbitrary code by design, and are trusted by everything downstream.
| Surface | Why |
|---|---|
| Pipeline definition changes | A modified workflow file is arbitrary code execution with production credentials |
| Secret access anomalies | A job reading secrets it has never read before |
| Self-hosted runner compromise | Long-lived, credential-rich, rarely monitored |
| Dependency changes | Typosquats, newly introduced transitive dependencies, maintainer changes |
| Artifact signing failures | Unsigned or mis-signed artifacts reaching a registry |
| Branch protection modification | Disabling review is the precondition to injecting code |
Framework implication. The detection repository described in Detection as Code is itself in this category. A program that automates detection deployment has created a new high-value target and MUST monitor it. Apply the framework to itself.
Operational technology¶
Where the framework applies with the most modification.
| Difference | Consequence |
|---|---|
| Availability outranks confidentiality | Automated containment is usually forbidden. RSP-3 pre-authorisation is typically "none" |
| Protocols are deterministic | Baselining works unusually well; deviation is meaningful |
| Systems cannot be patched or instrumented | Detection is almost entirely network-based and passive |
| Change is rare and scheduled | Any unscheduled change is high-signal |
| Safety consequences are physical | Response playbooks must involve engineering and safety authorities, not only IT |
Use the same lifecycle. Change the response engineering assumptions: RSP-3
authority, escalation paths and containment options all differ fundamentally.
AI and machine learning systems¶
New surface, and the one most likely to date this framework if omitted. Map
threats using MITRE ATLAS alongside ATT&CK; the detection schema supports
atlas_techniques for this purpose.
Two distinct problems¶
1. Attacks on AI systems the organization operates.
| Surface | Why |
|---|---|
| Prompt injection reaching a tool-enabled agent | Indirect injection via retrieved content is the dominant practical attack |
| Agent tool invocation anomalies | An agent calling tools or APIs outside its expected pattern |
| Model or system prompt extraction | Repeated probing; unusual output volume |
| Training and RAG data poisoning | Unauthorized writes to a corpus or vector store |
| Model artifact tampering | Changes to weights or model files outside the deployment pipeline |
| Inference cost anomalies | Resource abuse; also an early indicator of automated probing |
The critical framing: an AI agent with tool access is a privileged identity. It authenticates, it holds permissions, and it acts. Treat it as one. Give it an identity in the asset inventory, score it in the planning rubric, monitor its authorization changes and its actions, and give it a containment procedure. Most organizations currently do none of this.
2. Attacks that use AI.
Adversaries using generative tooling produce higher-quality lures and faster tooling iteration. This does not create new techniques so much as it degrades detections that relied on poor adversary craft. Detections whose implicit signal was "badly written English" or "unusual binary structure" have lost efficacy and should be re-scored for robustness.
Framework implications¶
- Add AI systems to the telemetry inventory (
TEL-3). Most have none today. - Agent action logs are a required log source for any agent with write access.
- Expect this section to change faster than any other. It is versioned with the specification for that reason.
Applying the framework across surfaces¶
The lifecycle does not change. What changes per surface is:
| Element | What to re-examine |
|---|---|
| Asset criticality | The unit of value: identity, workload, dataset, pipeline, agent |
| Telemetry availability | Frequently the binding constraint; sometimes a procurement problem |
| Robustness | API-based surfaces offer more invariant detections than endpoints |
| Response authority | OT and production cloud constrain automated containment |
| Review cadence | Faster-changing surfaces need shorter cadences |
The lifecycle itself is the same in every environment. A consent grant, a container escape, an IAM policy change and an agent tool invocation each need a business driver, a hypothesis, telemetry, logic, a test, a response and a review date.
In brief¶
- Identity is now the primary attack surface. Many significant intrusions involve no malware and no endpoint compromise.
- Cloud control planes, SaaS applications and pipelines are attacked through sequences of authorized API calls, which demand different detection logic from endpoint work.
- Telemetry availability is often the binding constraint, particularly for SaaS, and is best addressed at procurement.
- AI agents with tool access are best treated as privileged identities, with their own inventory entry, monitoring and containment procedure.
What comes next¶
With feasibility established, the lifecycle moves to the detection engineering phase: turning confirmed telemetry into detection logic that states its intent, handles exceptions, and is tested before release.