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PatternsProgram decision hijackingContext attacks

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.

Tagssecurityguardrailspatterns

From the Jev directory

An evaluation of prompt injection against Jev's typed probabilistic decisions using 510 reconstructed InjecAgent cases. Malicious content shifts action probabilities but rarely flips Jev to the attacker's target; score-feedback attacks raise fresh-run success from 1.8% to 3.5%.
Jev Practices & PatternsArticle#community#research#arxiv
Community
An automated framework that traces adversarial context through Jev-backed program decisions to downstream effects. Across 228 real-world Jev applications and 2,273 test cases, 81.5% show decision flips, 98.6% with potential security impact, and Decision Flip Rate beats the strongest baseline by 50.4 points.
Jev Benchmarks & EvaluationsArticle#community#research#arxiv
A controlled adversarial comparison of Jev against five GPT and GLM judges and two local classifiers under identical payloads and policies. Jev is the most robust on input moderation and the fastest overall, but detects only 62% of phishing emails and flags the most benign requests.
Jev Benchmarks & EvaluationsArticle#community#research#arxiv
Community
JevOut shows short background context additions can flip correct decisions in four systems including Jev across seven datasets. Within 64 accepted evaluations per decision, additions redirect 61.4%-73.2% of initially correct decisions toward a wrong option fixed in advance.
Jev Practices & PatternsArticle#community#research#arxiv
A systematic study of Jev's security and privacy implications using the official API and NanoJev, a local model with controllable training data. It adapts prompt injection, adversarial suffixes, and poisoned training data, runs inference attacks against typed outputs, and maps dual uses.
Jev Practices & PatternsArticle#community#research#arxiv

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