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Ephemeral GenAI SIEM: A Serverless, Graph-Driven Approach to Security Event Management

By Dinis Cruz and ChatGPT Deep Research · · 27 min read

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Contents · 8 sections
  1. Executive Summary
  2. Introduction: Rethinking SIEM for Scale and Context
  3. Design Principles of an Ephemeral GenAI SIEM
  4. Architecture Overview
  5. Workflow Example: Investigating a Malware Incident
  6. Technology Stack and Implementation
  7. Benefits and Future Outlook
  8. Conclusion

Executive Summary

Security Information and Event Management (SIEM) tools have long been central to enterprise defense, but traditional SIEMs struggle with scale, context, and cost. They often ingest massive volumes of log data into centralized systems, generating thousands of alerts with little context – a high noise-to-signal ratio that overwhelms analysts. Moreover, conventional SIEM pricing models charge by data volume, forcing organizations to retain only a fraction of telemetry (often <10%) to control costs. The result is a brittle status quo: SIEMs tell you what happened, but not why it matters or what to do next.

This white paper introduces Ephemeral GenAI SIEM, a next-generation approach co-developed by Dinis Cruz and ChatGPT Deep Research. It leverages serverless computing, semantic knowledge graphs, and generative AI (GenAI) to redefine how security data is collected, analyzed, and acted upon. Key innovations and decisions include:

In summary, Ephemeral GenAI SIEM offers a fundamentally new, cloud-native blueprint for security monitoring: one that scales by not scaling (it only uses resources when needed), that is open and extensible (built on open-source graphs and cloud storage), and that provides deep intelligence by leveraging graphs and AI. This white paper details the motivation, architecture, and workflow of this solution, demonstrating how it can drastically improve detection and response capabilities while controlling costs and complexity.


Introduction: Rethinking SIEM for Scale and Context

Traditional SIEM platforms were originally designed to aggregate logs into a central store, correlate events, and generate alerts for security teams. This model made sense in the early 2000s, but it is straining under the weight of modern IT environments. Organizations today deal with exploding data volumes, diverse infrastructure (cloud, on-prem, IoT, BYOD), and advanced threats that mutate and move laterally. In this landscape, conventional SIEMs reveal several critical shortcomings:

In short, the classic SIEM approach is showing its age. As one industry observer put it, “You’re collecting logs, but not catching threats.” The gap between data collection and actionable intelligence is widening. To close this gap, a new approach is needed – one that can economically harness all relevant data, provide rich context and explanations, and flexibly adapt to new data sources and attack techniques.

Design Principles of an Ephemeral GenAI SIEM

Ephemeral GenAI SIEM is designed from the ground up to address the above challenges. It is not a single monolithic product, but rather an architecture pattern and workflow enabled by cloud infrastructure and AI. The following core principles guide its design:

These principles set the stage for a SIEM that is cloud-native, intelligent, and laser-focused on providing actionable security insight rather than a flood of raw data. Next, we dive into the architecture that realizes these principles, and we illustrate the workflow with a concrete example.

Architecture Overview

At a high level, the Ephemeral GenAI SIEM can be visualized as a pipeline that starts from raw, distributed data sources and ends with consolidated security knowledge (alerts, graphs, and reports), with several transformation phases in between. Key architectural components include:

1. Data Sources and Connectors: These are the various origins of security data, which can be anything from traditional log files and SIEM feeds to API endpoints, message queues, or even screenshots and emails. Examples include:

Each source might have a dedicated connector function that knows how to retrieve data from it (using APIs, database queries, or by reading files from storage). Connectors are typically small, stateless functions that load raw data for a given query or time range (the Load in LETS). For efficiency, connectors might pull data in parallel if multiple sources are needed.

2. Persistent Data Lake (Object Storage as Database): All data, once pulled, is stored in a cloud object storage (like S3) in a structured way. We treat this storage as our source of truth database. For example, when fetching an hour of Windows Event Logs related to a host, the connector might save a file raw/hostXYZ/2025-06-18T12-13_events.json in the bucket. This persistent layer decouples data acquisition from processing – once data is in the lake, subsequent pipeline stages work off those saved files, not the live source. This also means if the same data is needed again (for another analysis or due to a pipeline change), we can reuse it without another external fetch. All data is stored in an open format (JSON, CSV, PCAP, etc.) to avoid vendor lock-in and ensure longevity. Organizing the storage by data source and time (and possibly by incident/case) makes it easier to manage and purge when appropriate.

3. LETS Processing Stages: As described, each processing stage takes input from the storage, does some computation, and writes output back. In practice, we implement stages as either serverless functions or containerized jobs orchestrated by an ephemeral framework (could be AWS Step Functions, a Kubernetes job runner, or a simple orchestrator script). The major stages in our SIEM pipeline might include:

All these stages are orchestrated in a serverless fashion. For instance, an initial trigger could be an alert from an EDR system hitting a webhook; that launches a coordinator function which kicks off the necessary connectors and stages for that host and alert. Or an analyst could manually initiate an investigation via a web interface by selecting an alert of interest, which triggers the pipeline. Under the hood, something (could be as simple as a Python script using AWS SDK, or a Step Functions state machine) coordinates the sequence: fetch data, wait for storage, parse, assemble graph, etc. Because each step writes to storage and can be stateless, the pipeline can tolerate variations – e.g., if one data source is slow, it doesn’t derail the whole process; the rest just waits for that file to appear.

Use of Open-Source and Standard Tools: Notably, this architecture leans heavily on open technologies. The graph database (MGraph-AI) is open source, the data formats are open (JSON, Markdown), and the orchestration can be built with standard cloud services or workflow engines. This avoids lock-in to any particular SIEM vendor. The philosophy is that the knowledge (graphs, data) is the valuable output, and it lives in portable form, while the processing logic can be adapted or reimplemented as needed. Organizations can extend or customize the pipeline by adding their own stages or swapping components (for example, using a different LLM or an internal ML model at the enrichment stage) without breaking the overall framework.

Now, to ground this in reality, let’s walk through an example incident to see how all these pieces come together.

Workflow Example: Investigating a Malware Incident

Consider a scenario faced by a SOC in 2025: an alert comes in that malware was detected on an employee’s laptop. This could originate from an endpoint protection platform (EPP/EDR) like Microsoft Defender or CrowdStrike, which flags a malicious file execution. In a traditional setup, this alert would show up in the SIEM with perhaps a short description and some hashes or file paths. It would be up to an analyst to investigate further by querying various logs. In our Ephemeral GenAI SIEM, however, the response is largely automated and far more comprehensive. Here’s how it unfolds step by step:

Step 1: Alert Ingestion and Initial Graph Node Creation The moment the malware detection alert is generated by the endpoint, it triggers our pipeline. This could be via a webhook from the EDR to our cloud function or a scheduled poll of the EDR’s alerts API. The first thing we do is create a graph node representing the alert event in our knowledge graph. This node might have attributes like alert_id, malware_name (if known), file_hash, host_name, timestamp, and EDR_tool (source). We save this initial evidence in our storage (e.g., graph/cases/incident123/alert.json). This node is essentially a placeholder that says “We have an alert about malware X on host Y at time T.” It’s the starting point of our investigation graph.

Step 2: Identifying Relevant Data Sources Next, the system determines which data sources might hold relevant information for this alert. Based on the alert details, it knows:

Using this, the pipeline compiles a list of sources to query, for example:

Not all of these will always be needed, but the system makes an informed guess of what could be useful. Importantly, it doesn't yet collect everything everywhere; it focuses on this host, this user, and this time slice.

Step 3: Data Retrieval (Load Phase) For each identified source, a connector function is invoked. These run in parallel where possible. They use the source’s native interface to get data:

As each connector gathers data, it writes the raw results to our S3 storage under a unique path for this incident. For example:

case123/raw/EDR_HOST123.json
case123/raw/WinLogs_HOST123_0600-0630.log
case123/raw/Proxy_Host123_0600-0630.csv
case123/raw/VirusTotal_abc123.json
...

Some data might be large (e.g., logs), but we’re only pulling a time-bounded slice. If a source is unavailable or returns nothing, that is noted (and can be flagged as a gap for later).

Step 4: Extraction and Graph Construction (Extract & Transform Phases) Now parsing and interpreting begins. For each raw data file:

At this point, we have constructed a knowledge graph that sprawls across multiple data sources but is centered on our incident. It might look like:

User[Bob] --owns--> Host[HOST123] --hasProcess--> Process[malware.exe] --fileHash--> File[abc123]
User[Bob] --received--> Email[ID456] --link--> Domain[evilmalware.com]
Host[HOST123] --made HTTP request--> Domain[evilmalware.com]
Domain[evilmalware.com] --hosted file--> File[abc123]
File[abc123] --is type--> MalwareFamily[AgentX]
File[abc123] --detectedBy--> Alert[EDR-123] (the original alert node)
Host[HOST123] --hasVulnerability--> Vulnerability[CVE-2024-XXXX]
...

Every node/edge also carries metadata like timestamp (for events), source reference (which raw log or record supports it), etc. This graph is saved as case123/graph/merged_graph.json for further use.

Step 5: Correlation and Hypothesis Linking With all pieces in the graph, the system now correlates the sequence of events. Often this simply emerges from the graph connections: we can see an email led to a download which led to execution which led to an alert. However, there might be missing links or multiple possibilities. For example, if we didn’t find the email, we might have the download but not how it was initiated. In such cases, we could query other sources (maybe the user visited that URL via web browser rather than email – we might then check browser history logs or DNS logs). The pipeline can use an LLM here to identify any apparent gaps or suggest additional pivots: e.g., "We saw a malicious file download, but no email – maybe the user navigated there manually or via a website. Check web proxy logs further back or DNS logs." This might prompt an additional data fetch (going back to Step 3 for another round). The iterative nature means the investigation can deepen as needed, akin to a human analyst following intuition, but guided by the AI to not overlook paths.

Assuming we have a fairly complete graph, the system can then piece together a narrative. It identifies chains of events. In our example, one chain might be: Email -> User click -> Domain -> File download -> Malware execution -> EDR detection. This can be mapped to the MITRE ATT&CK framework stages: Recon (email phishing) -> Initial Access (user clicks link) -> Execution (malware runs) -> C2 (if the malware connected out, not given here but if it did) -> Detection (response). The system can tag each part of the graph with MITRE technique IDs (if known) for standardized terminology.

Step 6: Enrichment of Risk and Impact Using the graph, we now enrich with business context (some of this we started in Step 4 with asset info, but here we focus on impact analysis):

Step 7: Reporting and Action Finally, the system generates outputs:

All the results are stored and indexed in the research hub (which could be the knowledge graph repository for all incidents). If a similar incident happens next month, the CISO can even query: "Have we seen evilmalware.com before?" and the system will find that domain node from this incident graph and show the past context. This historical memory, built on graphs, becomes incredibly valuable for threat hunting and retrospectives.

Step 8: Disposal and Reset Once the analysis is done and outputs are delivered, the ephemeral compute infrastructure used can be completely torn down. The data (graphs, raw logs) remains in the storage for future reference, but the analysis environment (containers, memory structures) is gone. If we need to revisit or redo analysis, we simply re-run the pipeline on the stored data or fetch new data. The system is ready to handle the next incident with a fresh set of functions, ensuring no cross-contamination of data in memory and optimal use of resources.

This example demonstrates how Ephemeral GenAI SIEM handles an incident in a way that contrasts sharply with a traditional SIEM workflow. Instead of an analyst manually pulling logs and piecing together clues for hours, the system assembled a comprehensive narrative in minutes, with full evidence attached. The analyst’s role shifts to validation and response decision-making, supported by the system’s findings. Crucially, this was done without pre-ingesting all corporate logs into a single system, and without maintaining a standing army of servers crunching data 24/7. The pipeline only spun up in response to the event, used targeted data to enrich context, and stood down after delivering insight.

Technology Stack and Implementation

To implement the Ephemeral GenAI SIEM, we leverage a combination of cloud services, open-source libraries, and custom code – much of which is developed in the open as part of Dinis Cruz’s research initiatives. Below are key components of the tech stack and how they contribute to the solution:

We ensure these calls are stateless and idempotent parts of the pipeline. Each LLM invocation is treated as a function: input data goes in, output data comes out. We do not rely on hidden model state or memory between calls. And if needed, we can log the prompts and responses for audit (especially important if using external APIs). If an LLM step is non-deterministic (slight variance in phrasing, for example), it doesn’t affect the integrity of the graph data since we enforce structure. In essence, we treat LLMs as powerful parsers and correlators under tight control.

The bottom line is that adding a new correlation rule or data source doesn’t require writing thousands of lines of Java and deploying a heavy app (as might be with older SIEM customizations). It can be as simple as writing a prompt or a few lines of Python, which our GenAI helpers and frameworks then integrate into the larger system. This encourages experimentation and quick iteration – essential for keeping up with evolving threats.

In practice, implementing this stack has been greatly accelerated by open-source contributions. For instance, the MGraph-AI library was released as open source, meaning anyone can use or contribute to it for their own GenAI+graph projects. The LETS pipeline concept was documented and shared, providing a template that others have begun to follow for similar deterministic AI workflows. This white paper itself, co-authored by Dinis Cruz and ChatGPT, demonstrates the no-code philosophy: using AI to articulate and refine the architecture.

Benefits and Future Outlook

Adopting the Ephemeral GenAI SIEM architecture yields numerous benefits for organizations striving to improve their security operations:

Future Outlook: This architecture opens the door to numerous future advancements. For instance:

Conclusion

The Ephemeral GenAI SIEM represents a bold re-imagining of security monitoring. By harnessing the power of cloud scalability, the expressiveness of knowledge graphs, and the intelligence of generative AI, it addresses the long-standing pain points of traditional SIEMs: high cost, overwhelming noise, and lack of context. Our design choices – from using S3 as a database, to treating every step as a reproducible data transformation, to keeping the entire system disposable – were driven by practical experiences in building AI-assisted systems that needed transparency and reliability.

In implementing this system, we've adhered to a philosophy of openness (open formats, open source tools) and collaboration between human experts and AI. The result is a SIEM that scales by doing less upfront (no more ingest-all-the-things), and accomplishes more by thinking smarter – connecting dots that were previously siloed and presenting solutions, not just alerts.

For technical CISOs and security leaders, this approach offers a path to finally escape the trade-off between comprehensive security visibility and operational feasibility. You no longer have to accept that “we only use 10% of our data” or that “the SOC is drowning in false alerts.” With Ephemeral GenAI SIEM, you can truly use all your data in a targeted way, cut through the noise with AI-driven context, and do so on infrastructure that flexibly scales with your needs. It transforms the SIEM from a static log aggregator into a living, breathing analytical assistant that grows in knowledge every day.

In publishing this white paper, our hope is to share a blueprint that others can adapt and build upon. All the core components discussed are available through open research and code (for example, the MGraph-DB library and example pipelines). We encourage the community to experiment with these ideas, contribute improvements, and collectively push the state of the art in security operations. The challenges we face in cybersecurity are immense and ever-changing, but with approaches like this – combining the best of human strategy and AI capability – we have a fighting chance to stay ahead.

Dinis Cruz and ChatGPT Deep Research, June 2025

Sources: The concepts and implementations described here are based on Dinis Cruz’s open research on deterministic GenAI pipelines and semantic graphs, industry analyses of SIEM limitations, and the practical lessons learned from building GenAI-powered security and news analysis platforms.

Released under CC BY 4.0. First published on docs.diniscruz.ai; this page as markdown.