ASCII smuggling
AssessTechniques
A text-obfuscation technique that encodes readable content using invisible Unicode tag characters.
Why it's here
Placed in Assess: 2 article(s) of evidence from 2 source(s), led by security coverage, with 0 in the last 30 days. Confidence 37%.
Evidence (2)
- 8The New Stack·9/4/2026securityMicrosoft Spotlights Unicode Tag Phishing Tactic
Microsoft said a phishing campaign used invisible Unicode tag characters to break up keywords such as “funding,” “loan,” and “credit,” helping messages evade spam filters and ML-based classifiers. The same character-range trick can also affect AI and NLP systems because tokenizers may process the text differently than humans see it, so Microsoft recommends removing or comparing tagged text before it reaches models.
- 7Ars Technica AI·9/4/2026securitySpammers adopt ASCII smuggling to bypass email filters
A technique originally used to hide prompt injections from AI systems is now being used by spammers to evade email platform filters. The method relies on invisible Unicode tag characters that computers can read but people typically cannot see, allowing malicious text to slip past detection.