The Marriage of AI and Cybersecurity — From Network Detection to SOC Automation
Introduction: A New Philosophy for Cyber Defense
Vectra AI is a pioneer in applying Artificial Intelligence (AI) to cybersecurity with a core philosophy: effective cyber defense requires tight collaboration between security researchers and data scientists.
Their goal is to move beyond:
- reactive, signature-based security
- brittle, easily-evaded anomaly rules
…and instead design generalizable models that capture attacker behavior at an abstract level.
This document outlines:
- how data representation shapes detection performance
- how large language models reshape SOC workflows
- how Vectra AI blends symbolic reasoning + LLMs to work toward SOC automation
Part 1: Foundations of AI-Driven Detection
1. The Representation Problem
The success of any ML system depends heavily on:
- how data is represented, and
- which model architecture is chosen
Linear Models + Domain Expertise
- Data scientists alone may not solve a complex security problem with a simple model.
- Security researchers alone may create fragile signatures.
- Vectra's solution: researchers guide data scientists to transform raw data so that simple linear models can cleanly separate malicious from benign traffic.
Modeling Time in Security
Certain threat behaviors are inherently temporal (e.g., network flows).
Traditional approach:
- Random Forest with handcrafted features
- Failed for advanced C2 detection
Breakthrough: RNNs
RNNs model multi-dimensional time series and detect abstract attacker behavior patterns.
C2 Example:
Attackers often:
- reverse normal communication flow
- create unseen C2 tools
RNNs generalized to completely new C2 frameworks years after initial training.
2. Graph Structures for Privilege Anomaly Detection
Privilege anomaly = user's observed privilege differs from intended privilege.
Solution:
- Build graph of users, hosts, services
- Compute observed privilege (PageRank-like)
- Flag deviations
Useful for:
- lateral movement
- privilege escalation
- BloodHound-style mapping attacks
Part 2: The LLM Revolution & Reliability Challenge
System 1 vs. System 2 Reasoning
LLMs excel at:
- fast
- intuitive
- pattern-based reasoning
But struggle with:
- logical
- deliberate
- multi-step reasoning
Example hallucination: "Miami, Florida has state income tax." (incorrect)
Failure Modes in LLM Security Systems
1. Specification Issues
Poor design or unclear requirements.
2. Inter-Agent Misalignment
Agents misinterpret each other.
3. Task Verification Failures
Outputs go unvalidated (e.g., invalid IP treated as valid).
Injecting System 2 Reasoning
1. Chain-of-Thought Prompting
Ask LLM to show steps before the answer.
2. Self-Reflection Agents
Verifier checks generator output.
3. Multi-Agent Systems
Planning agent, execution agents, verification agents.
Part 3: LLMs Inside the Vectra SOC
Current LLM Use Cases
- Natural language → SQL
- Automated incident summaries
- TL;DR for long logs or email threads
- Normalization of messy external data (e.g., LinkedIn job titles)
Vision for Full SOC Automation
Hybrid: LLMs + Symbolic Reasoning
LLMs handle fuzzy unstructured tasks.
Symbolic systems handle deterministic logic.
Structured Outputs:
All agent output must be JSON-structured and validated.
Adversarial Awareness:
LLMs are given both supporting and contradicting evidence to improve reasoning.
The Human Factor
Challenges
Analysts over-trusted LLM outputs.
Solutions
Add speed bumps and flags requiring human review.
Outcome
- Big productivity boost
- AI behaves like "extra analysts"
- Full automation still far out due to risk of errors
Conclusion
To succeed with AI in cybersecurity:
- Try classical methods first
- Introduce AI when traditional approaches fail
- Combine LLMs with symbolic reasoning
- Prioritize reliability
- Structure and verify all agent outputs
The future of SOC is not replacing analysts — it is amplifying them.