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Security2026-04-21 · source-backed

Seven Cross-Domain Techniques for Prompt Injection Detection.

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Story

New paper argues both regex and fine-tuned classifiers share critical failure modes for detecting prompt injection. Regex misses paraphrased attacks, classifiers get bypassed at >50% success rates by adaptive adversaries. The paper proposes seven detection techniques from fields outside NLP. If you're building agent pipelines processing untrusted input, pattern matching alone won't save you.

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2026-04-21-seven-cross-domain-techniques-for-prompt-injection-detection
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source-backed, canonical briefing excerpt