What is prompt injection in LLMs?

It's tricking an AI by sneaking fake instructions into user messages, like XML tags mimicking system prompts, to leak secrets or override rules.

Which LLMs are vulnerable to prompt injection?

The report names none specifically — vendors notified — but three commercial ones leaked JSON payloads in tests; seven like Claude and GPT resisted.

Sanitize inputs: strip XML tags pre-model, use strict role formats, or deploy open-source firewalls like Parapet for fast, cheap detection.

💻 Programming Languages

I sent the same sneaky prompt injection to ten LLMs. Three dumped their guts in JSON. Here's why that's a red flag for AI hype.

Open Source Beat Apr 11, 2026 3 min read

Three LLMs leaked full context via simple XML prompt injection; seven resisted. 𝕏
Hallucinated rules and structured JSON make exploits stealthier than raw text dumps. 𝕏
Open-source Parapet fixes it cheaply — input sanitization works, vendors just lag. 𝕏

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#AI vulnerabilities #LLM security #Parapet firewall #open source firewall #prompt injection

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Originally reported by Dev.to