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Field Intel

Fifty-six dispatches on AI security, red-teaming AI, AI for defence and the cybersecurity fundamentals that never go out of style. All by Rajnish Kumar.

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Showing 56 dispatches

AI Security
RAJNISH KUMAR · 08 Aug 2026 · 7 min

Prompt Injection: The New SQL Injection of the AI Era

Untrusted text reaching an LLM is the injection flaw of this decade. Here is how prompt injection works, why it is so hard to fix, and what actually reduces the blast radius.

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AI Security
RAJNISH KUMAR · 04 Aug 2026 · 8 min

Securing the RAG Pipeline: Where Retrieval Meets Risk

Retrieval-augmented generation pulls in documents you don't fully control. Every one of them is an instruction the model might obey.

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AI Security
RAJNISH KUMAR · 31 Jul 2026 · 8 min

Data Poisoning: Defending Your Training Set From Sabotage

If an attacker can slip crafted samples into your training data, they can plant behaviour that survives into production. Poisoning is a supply-chain problem for models.

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AI Security
RAJNISH KUMAR · 27 Jul 2026 · 7 min

When Models Leak Their Data: Inversion and Membership Inference

A trained model is a lossy compression of its data. With the right queries, attackers can reconstruct fragments of it or prove someone was in the set.

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AI Security
RAJNISH KUMAR · 23 Jul 2026 · 9 min

The OWASP Top 10 for LLM Applications, Explained

OWASP mapped the ten risks that matter most for large language model apps. Here is a practitioner's tour of each, with what to actually do about it.

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AI Security
RAJNISH KUMAR · 19 Jul 2026 · 7 min

Guardrails, Not Handcuffs: Designing Safe LLM Output Filters

Guardrails are the seatbelts of LLM apps. Done well they catch harm; done badly they break the product and still miss attacks.

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AI Security
RAJNISH KUMAR · 15 Jul 2026 · 8 min

Securing AI Agents: When Your Chatbot Can Take Actions

The moment an LLM can call tools, send emails or move money, a prompt becomes a command. Agentic AI turns content risks into action risks.

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AI Security
RAJNISH KUMAR · 11 Jul 2026 · 7 min

Supply-Chain Risk in the Age of Model Hubs

You didn't train it, you downloaded it. Pre-trained models, datasets and pip packages are a trust chain most teams never audit.

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AI Security
RAJNISH KUMAR · 07 Jul 2026 · 7 min

Adversarial Examples: Fooling Computer Vision With a Sticker

A few carefully placed pixels can make a model call a stop sign a speed limit. Adversarial examples are perturbations invisible to us but decisive to the model.

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AI Security
RAJNISH KUMAR · 03 Jul 2026 · 6 min

Secrets Management for AI Applications

AI apps sprinkle API keys, vector DB creds and model tokens everywhere. Prompts and logs then quietly exfiltrate them.

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AI Security
RAJNISH KUMAR · 29 Jun 2026 · 7 min

Jailbreaks Explained: Why 'Ignore Previous Instructions' Still Works

Every model ships with rules and every week someone talks it out of them. Jailbreaks reveal the gap between alignment and enforcement.

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AI Security
RAJNISH KUMAR · 25 Jun 2026 · 7 min

Protecting Vector Databases From Embedding Inversion

Embeddings feel anonymous. They aren't. Given the vectors, an attacker can often reconstruct the text they came from.

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AI Security
RAJNISH KUMAR · 21 Jun 2026 · 8 min

Threat Modeling Machine Learning Systems

You threat-model your web app. Your model deserves the same. ML systems have attack surfaces classic threat models never enumerate.

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AI Security
RAJNISH KUMAR · 17 Jun 2026 · 6 min

Shadow AI: The Unsanctioned Tools Draining Your Data

Your staff are already pasting source code and customer data into chatbots you never approved. Shadow AI is the new shadow IT.

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Testing AI
RAJNISH KUMAR · 13 Jun 2026 · 8 min

AI Red Teaming 101: A Field Guide to Breaking Language Models

Red teaming an LLM is not the same as pentesting a web app. Here is how to think like an adversary against a model that talks back.

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Testing AI
RAJNISH KUMAR · 09 Jun 2026 · 8 min

Building Your First LLM Penetration Testing Methodology

Ad-hoc poking finds ad-hoc bugs. A repeatable methodology finds the ones that matter, every time, and proves coverage.

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Testing AI
RAJNISH KUMAR · 05 Jun 2026 · 7 min

Fuzzing Machine Learning Models: Inputs You Never Expected

Fuzzing broke C programs for decades. Pointed at models, it surfaces the weird inputs that make them crash, leak or misbehave.

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Testing AI
RAJNISH KUMAR · 01 Jun 2026 · 6 min

Testing for Prompt Leakage: Extracting the System Prompt

The system prompt is supposed to be invisible. Often it is one clever question away from full disclosure - along with its secrets.

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Testing AI
RAJNISH KUMAR · 28 May 2026 · 7 min

Evaluating Chatbot Guardrails With Automated Attack Suites

One tester and a coffee will not cover a guardrail's failure surface. Automated attack suites test thousands of variations while you sleep.

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Testing AI
RAJNISH KUMAR · 24 May 2026 · 8 min

Testing AI Agents for Tool Abuse and Privilege Escalation

Give an agent tools and you give an attacker a toolbox. Testing agentic AI means testing what it can be tricked into doing.

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Testing AI
RAJNISH KUMAR · 20 May 2026 · 7 min

Bias and Fairness Testing as a Security Concern

A biased model is not just an ethics problem - it is an exploitable one. Fairness gaps become attack surface and liability.

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Testing AI
RAJNISH KUMAR · 16 May 2026 · 7 min

Red Teaming Multimodal Models: Images That Speak Injection

When a model can read images, an attacker can hide instructions inside a picture. Multimodal expands the injection surface dramatically.

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Testing AI
RAJNISH KUMAR · 12 May 2026 · 7 min

Measuring Hallucination: Test Design for Factual Integrity

A confident wrong answer can be worse than no answer. To manage hallucination you first have to measure it rigorously.

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Testing AI
RAJNISH KUMAR · 08 May 2026 · 7 min

Testing RAG Systems for Indirect Prompt Injection

Your RAG app trusts its documents. Plant one malicious paragraph in the knowledge base and the model works for the attacker.

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Testing AI
RAJNISH KUMAR · 04 May 2026 · 7 min

Benchmarking LLM Security With Open Frameworks

You don't have to build every probe from scratch. Open tooling like garak and PyRIT industrialise LLM security testing.

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Testing AI
RAJNISH KUMAR · 30 Apr 2026 · 6 min

Regression-Testing Your Guardrails After Every Model Update

A model update can silently reopen a bug you closed months ago. Without regression tests, safety quietly rots.

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Testing AI
RAJNISH KUMAR · 26 Apr 2026 · 8 min

Threat-Led AI Penetration Testing: From Scope to Report

A real AI pentest is scoped, threat-led and evidence-driven - not a weekend of jailbreak screenshots.

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Testing AI
RAJNISH KUMAR · 22 Apr 2026 · 6 min

Testing for Denial-of-Wallet: Resource Exhaustion in LLM Apps

You can't DDoS a serverless AI app off the internet - but you can bankrupt it. Denial-of-wallet is model DoS with a billing twist.

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AI for Security
RAJNISH KUMAR · 18 Apr 2026 · 7 min

Using LLMs to Accelerate Vulnerability Triage

Scanners produce noise; humans burn out. LLMs can pre-triage findings so analysts spend attention where it counts.

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AI for Security
RAJNISH KUMAR · 14 Apr 2026 · 7 min

AI-Assisted Code Review: Catching Bugs Before They Ship

AI reviewers never get tired at line 4,000. Used well they widen coverage; used blindly they rubber-stamp vulnerabilities.

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AI for Security
RAJNISH KUMAR · 10 Apr 2026 · 8 min

Machine Learning for Anomaly Detection in Network Traffic

Signatures catch what you've seen. Anomaly detection aims at what you haven't - the price is false positives you must engineer around.

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AI for Security
RAJNISH KUMAR · 06 Apr 2026 · 7 min

Automating Reconnaissance With AI (Responsibly)

AI can read the whole attack surface faster than any analyst. That power cuts both ways, so it comes with rules of engagement.

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AI for Security
RAJNISH KUMAR · 02 Apr 2026 · 7 min

LLMs in the SOC: Summarizing Alerts Without Losing Signal

A SOC drowns in alerts. LLMs can summarise and correlate them - as long as the summary never hides the one that matters.

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AI for Security
RAJNISH KUMAR · 29 Mar 2026 · 7 min

AI-Powered Phishing Detection: Beyond the Blocklist

Blocklists are always a step behind. Language models can read intent, catching the well-crafted lure a static filter waves through.

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AI for Security
RAJNISH KUMAR · 25 Mar 2026 · 7 min

Generating Better Test Cases With AI for Fuzzing Campaigns

Dumb fuzzers stumble on bugs by luck. AI-guided input generation reaches deep code paths a random mutator never would.

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AI for Security
RAJNISH KUMAR · 21 Mar 2026 · 7 min

Threat Intelligence at Scale: Letting AI Read the Firehose

No team can read every advisory, forum post and CVE. AI can - and can hand analysts the 1% that matters to them.

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AI for Security
RAJNISH KUMAR · 17 Mar 2026 · 7 min

AI for Log Analysis: Finding the Needle in Petabytes

Logs hold the evidence and the noise in equal measure. AI can cluster, baseline and narrate them so investigations start hours ahead.

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AI for Security
RAJNISH KUMAR · 13 Mar 2026 · 7 min

Copilots for Pentesters: Where They Help and Where They Hurt

An AI copilot can draft your payload, explain a protocol and waste an hour on a confident wrong turn. Knowing which is the skill.

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AI for Security
RAJNISH KUMAR · 09 Mar 2026 · 7 min

Detecting Malware With Machine Learning Classifiers

Polymorphic malware defeats hashes by design. ML classifiers learn the shape of malice - and attackers learn to reshape it.

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AI for Security
RAJNISH KUMAR · 05 Mar 2026 · 7 min

AI-Driven Deception: Smarter Honeypots and Canary Tokens

Static honeypots fool no one for long. LLM-backed decoys can hold a conversation, keeping an intruder busy and observed.

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AI for Security
RAJNISH KUMAR · 01 Mar 2026 · 6 min

Natural Language to Detection Rules: Writing Sigma With AI

Describe the behaviour in plain English; get a draft detection back. AI is shrinking the gap between an idea and a working rule.

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AI for Security
RAJNISH KUMAR · 25 Feb 2026 · 8 min

The Analyst Augmented: Building an AI Assistant for Blue Teams

The goal isn't to replace the analyst - it's to give them a tireless junior who reads everything and forgets nothing.

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Cyber Defense
RAJNISH KUMAR · 21 Feb 2026 · 7 min

Zero Trust Explained Without the Buzzwords

Zero trust is not a product you buy - it is a principle: never trust, always verify. Here is what that means in practice.

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Cyber Defense
RAJNISH KUMAR · 17 Feb 2026 · 6 min

Why Multi-Factor Authentication Isn't Optional Anymore

Passwords fall daily to phishing and reuse. MFA is the single highest-leverage control most organisations still under-deploy.

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Cyber Defense
RAJNISH KUMAR · 13 Feb 2026 · 8 min

The Anatomy of a Ransomware Attack, Step by Step

Ransomware rarely detonates on day one. It is the loud finale of a quiet intrusion you could have caught days earlier.

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Cyber Defense
RAJNISH KUMAR · 09 Feb 2026 · 6 min

Password Hygiene in the Passkey Era

The password isn't dead yet, but passkeys are writing the obituary. Here is how to bridge the two worlds safely.

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Cyber Defense
RAJNISH KUMAR · 05 Feb 2026 · 8 min

Understanding the MITRE ATT&CK Framework

ATT&CK is the shared language of how attackers actually operate. Learn to read it and your detections stop being guesswork.

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Cyber Defense
RAJNISH KUMAR · 01 Feb 2026 · 7 min

Defense in Depth: Layering Controls That Actually Work

No single control holds forever. Defence in depth assumes each layer will fail and makes sure the next one catches it.

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Cyber Defense
RAJNISH KUMAR · 28 Jan 2026 · 7 min

Social Engineering: Hacking the Human Firewall

The easiest way past a firewall is to ask someone to open the door. Technology can't patch a helpful human.

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Cyber Defense
RAJNISH KUMAR · 24 Jan 2026 · 7 min

Cloud Misconfigurations: The Silent Breach Enabler

Most cloud breaches aren't clever exploits - they're an open bucket and a wildcard IAM policy nobody reviewed.

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Cyber Defense
RAJNISH KUMAR · 20 Jan 2026 · 7 min

Incident Response: The First 60 Minutes Matter Most

How you spend the first hour of an incident decides how the next month goes. Panic is expensive; a plan is priceless.

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Cyber Defense
RAJNISH KUMAR · 16 Jan 2026 · 8 min

Securing the Software Supply Chain After SolarWinds

You don't just run your own code - you run everyone's. A single poisoned dependency can undo every other control.

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Cyber Defense
RAJNISH KUMAR · 12 Jan 2026 · 7 min

API Security: The Attack Surface Everyone Forgets

Your APIs do the real work and hold the real data - and they're often protected by little more than optimism.

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Cyber Defense
RAJNISH KUMAR · 08 Jan 2026 · 7 min

Deepfakes and Synthetic Media: The New Face of Fraud

Seeing is no longer believing. A cloned voice or a fabricated video call is now a viable path to a fraudulent wire transfer.

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Cyber Defense
RAJNISH KUMAR · 04 Jan 2026 · 7 min

Building a Security-First Culture in a Growing Company

Tools don't secure a company; people do. Culture is the control that scales when your headcount outpaces your policies.

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Cyber Defense
RAJNISH KUMAR · 31 Dec 2025 · 7 min

From Vulnerability to Patch: Running a Sane Remediation Program

Finding vulnerabilities is easy; fixing the right ones fast is the hard, unglamorous work that actually reduces risk.

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//: SIGNAL BOOST

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