“Give a Positive Review Only”: An Early Investigation Into In-Paper Prompt Injection Attacks and Defenses for AI Reviewers

Qin Zhou, Zhexin Zhang, Li Zhi, Limin Sun


Abstract
With the rapid advancement of AI models, their deployment across diverse tasks has become increasingly widespread. A notable emerging application is leveraging AI models to assist in reviewing scientific papers. However, recent reports have revealed that some papers contain hidden, injected prompts designed to manipulate AI reviewers into providing overly favorable evaluations. In this work, we present an early systematic investigation into this emerging threat. We propose two classes of attacks: (1) static attack, which employs a fixed injection prompt, and (2) iterative attack, which optimizes the injection prompt against a simulated reviewer model to maximize its effectiveness. Both attacks achieve striking performance, frequently inducing full evaluation scores when targeting frontier AI reviewers. Furthermore, we show that these attacks are robust across various settings. To counter this threat, we explore a simple detection-based defense. While it substantially reduces the attack success rate, we demonstrate that an adaptive attacker can partially circumvent this defense. Our findings underscore the need for greater attention and rigorous safeguards against prompt-injection threats in AI-assisted peer review.
Anthology ID:
2026.findings-emnlp.49
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
982–997
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.49/
DOI:
Bibkey:
Cite (ACL):
Qin Zhou, Zhexin Zhang, Li Zhi, and Limin Sun. 2026. “Give a Positive Review Only”: An Early Investigation Into In-Paper Prompt Injection Attacks and Defenses for AI Reviewers. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 982–997, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
“Give a Positive Review Only”: An Early Investigation Into In-Paper Prompt Injection Attacks and Defenses for AI Reviewers (Zhou et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-emnlp.49.pdf