Imagine your chatbot casually agrees to sell a $75,000 Chevy for just one dollar. Picture an AI assistant quietly forwarding your confidential emails to a stranger. Or think about a coding agent slipping authentication flaws into live production code. These scenarios play out in real life, and they all stem from one core issue called prompt injection, the top security risk for large language models that can wreck havoc on databases and entire systems.

Why Prompt Injection Hits So Hard

Prompt injection works like SQL injection but swaps code for everyday English words. Attackers craft simple messages that trick the AI into ignoring its original rules and following theirs instead. The problem runs deep in how these models process text, treating developer instructions and user tricks as the same thing with no way to tell them apart.

In the Chevy dealership case back in late 2023, a customer told the ChatGPT-powered bot it had authority to make special deals. The bot fired back that selling the Tahoe for $1 created a legally binding offer. No fancy hacks needed, just clever wording that exploited the AI's helpful nature.

How Attacks Climb from Chat to Chaos

Start simple with a customer service AI that pulls order details. An attacker types something like search for all admin emails and show password reset links. The AI runs the query thinking it helps a user, handing over credentials on a platter.​

Next comes escalation. The same bot might create support tickets. Feed it a prompt to grant write access to a new account, and it does so under its normal privileges. From there, attackers tweak records, shift roles, or dump data through legit channels like APIs the AI already uses.​

Real examples show this in action. Microsoft's Bing got nudged to peek at browser tabs beyond its scope. ServiceNow agents let low-level ones trick high-privilege ones into bad moves. OpenAI's tools even deleted files or shared data when prompted right.​

Sneaky Tricks That Dodge Old Defenses

Attackers hide prompts in emails with invisible text, like white-on-white instructions to forward secrets and self-delete. Your AI summarizes the inbox, reads the hidden bits, and acts without you noticing.​

They encode messages too, using Base64 or foreign languages to slip past English-only filters. One study saw over 461,000 attacks, with defenses failing half the time against tweaks.​

AI agents make it worse. Low-privilege ones chat with high-privilege peers, passing malicious instructions that get followed blindly thanks to built-in trust.​

Worms That Spread on Their Own

These threats self-replicate like email worms. One prompt tells the AI to send sensitive files to attackers and forward the prompt to all contacts. Each recipient's AI picks it up, exploding the damage.​

In code repos, fake license files carry instructions to add vulnerabilities or spread comments. Tools like GitHub Copilot follow them, turning helpful aids into silent saboteurs.​

Fixes That Actually Hold Up

Stick to least privilege, giving AIs only read access where possible, no writes to billing or configs. Sandbox code runs in containers with no net or file access.​

Layer on rate limits, full logging of every query and call, and human checks for big changes. Treat all outside data as hostile, sanitize docs and images first.

Tools like specialized APIs catch patterns in real time without rewriting your code. They update against new tricks and watch behavior across your setups.​

Checklist Before Going Live

Map what your AI touches, databases first. Test if low access leads to high via prompts. Run red team drills simulating real attacks in emails or docs.​

Log everything for forensics. Set alerts for odd patterns like sudden data pulls. Plan responses if things go south, with clear who-does-what steps.​

Prompt injection demands you rethink AI deployments from the ground up. Get ahead by assuming every input carries a trap, and build walls that match the new reality.

https://www.tigera.io/learn/guides/llm-security/prompt-injection