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Obfuscated Token Reconstruction via Character Substitution - ATR-2026-02020 (9c340bcd-68cf-5ceb-a43e-e763ca7b794e)

Detects prompt injection attempts that smuggle a forbidden or filter-triggering token past input screening by first presenting it broken (via a placeholder, homoglyph, or partial spelling) and then instructing the model to reconstruct it at generation time using explicit "replace X with Y" / "remove X" character- substitution instructions. The attack relies on the target string (e.g. a forced "PWNED"-style compliance marker) never appearing intact in the raw prompt, only being assembled by the model's own output logic after following the substitution recipe. Detection targets the substitution-instruction shape plus the resulting trailing token fragment, not the broken placeholder itself.

Cluster A Galaxy A Cluster B Galaxy B Level
LLM Prompt Injection (19cd2d12-66ff-487c-a05c-e058b027efc9) MITRE ATLAS Attack Pattern Obfuscated Token Reconstruction via Character Substitution - ATR-2026-02020 (9c340bcd-68cf-5ceb-a43e-e763ca7b794e) Agent Threat Rules 1
LLM Jailbreak (172427e3-9ecc-49a3-b628-96b824cc4131) MITRE ATLAS Attack Pattern Obfuscated Token Reconstruction via Character Substitution - ATR-2026-02020 (9c340bcd-68cf-5ceb-a43e-e763ca7b794e) Agent Threat Rules 1