Decision hijacking
An attack that steers a typed decision through attacker-controlled context — tool output, retrieved text, or an option name — while every request and response stays schema-valid.
- Category
- Patterns
- Also known as
- Program decision hijacking, Context attacks
- Related terms
- 4
- Directory entries
- 5
- Docs
- —
- Added
- 2026-10-14
Definition
Because Jev consumes program context and returns typed answers, an attacker does not need the model to emit text: a poisoned tool result, a retrieved passage, or a crafted option label can flip the decision while the schema stays intact. One automated framework traced this across 228 real Jev applications and found 81.5% showed decision flips, 98.6% with potential security impact, and the tested defenses helped little.
The published attacks split into context channels and interface channels: a sentence asking only why someone might make a harmful request bypassed 9% of moderation blocks, option-name swaps flip answers without touching definitions, and interface attacks tilt probabilities without any payload in the state. Mitigation starts with treating every context surface as untrusted input and testing flips with your real option lists, not generic prompts.
Related terms
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