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CommunityJev Benchmarks & Evaluations
JevBreak: Your Model, Their Decision
arXiv paper presenting Slot Attack, a black-box attack that appends text to evidence to steer decision models toward an attacker-chosen wrong option. Evaluates seven decision models on 16 Decision Bench tasks across seven domains.
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- Article
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- Added
- Nov 2026
Highlights
- Slot Attack appends text assembled from named components to steer predictions toward an attacker-selected incorrect option.
- Reports 32-99% success on initially correct decisions across seven decision models.
- Uses only returned label probabilities, with a median of 17-72 queries per successful attack.
- Models with near-identical accuracy differ by about 20 percentage points in attack success.
- On about 20% of correct decisions for the JEV models, an attacker could force every available wrong answer.
Questions about this entry
Short answers drawn from the linked project or page.
Slot Attack is a black-box attack designed for decision models. It appends text assembled from named components to the evidence in order to steer predictions toward an attacker-selected incorrect option, relying solely on the label probabilities the model returns.
Seven decision models spanning hosted APIs, open-weight models and an encoder are evaluated on 16 tasks in seven domains from Decision Bench, targeting every wrong option across 240 text examples, or 990 targets per model.
The paper reports success rates of 32-99% on initially correct decisions. Accuracy and confidence do not reliably reveal the vulnerability, and models with near-identical accuracy on the sampled tasks differ by about 20 percentage points in attack success.
The method identifies effective component combinations with a median of 17-72 queries per successful attack, using only the label probabilities returned by the model.
No. The paper states that a confidence threshold does not reliably screen the attack out, and that accuracy and confidence do not reliably reveal the vulnerability.
Yes. The authors demonstrate forcing every available wrong answer on about 20% of correct decisions for the JEV models, 77% for gpt-6-luna and 98% for GLiNER2.5.
It concludes that a fixed answer set constrains a decision's form, not its source, and that robustness must be measured per model, per task and per version rather than assumed from output format.
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