Sneaky Bits: Advanced Data Smuggling Techniques (ASCII Smuggler Updates)
Summary
Researchers have discovered advanced data smuggling techniques using invisible Unicode characters (invisible text that computers can process but humans cannot see) to hide information in LLM inputs and outputs. The technique, called Sneaky Bits, can encode any character or sequence of bytes using only two invisible characters, building on earlier methods that used Unicode Tags and Variant Selectors to inject hidden instructions into AI systems.
Classification
Affected Vendors
Related Issues
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Original source: https://embracethered.com/blog/posts/2025/sneaky-bits-and-ascii-smuggler/
First tracked: February 12, 2026 at 02:20 PM
Classified by LLM (prompt v3) · confidence: 85%