Papers › Automatic and Universal Prompt Injection Attacks against Large Language Models

Automatic and Universal Prompt Injection Attacks against Large Language Models

7 Mar 2024arXiv:2403.04957archive 2025-07-28

Xiaogeng Liu, Zhiyuan Yu, Yizhe Zhang, Ning Zhang, Chaowei Xiao

Large Language Models (LLMs) excel in processing and generating human language, powered by their ability to interpret and follow instructions. However, their capabilities can be exploited through prompt injection attacks. These attacks manipulate LLM-integrated applications into producing responses aligned with the attacker's injected content, deviating from the user's actual requests. The substantial risks posed by these attacks underscore the need for a thorough understanding of the threats. Yet, research in this area faces challenges due to the lack of a unified goal for such attacks and their reliance on manually crafted prompts, complicating comprehensive assessments of prompt injection robustness. We introduce a unified framework for understanding the objectives of prompt injection attacks and present an automated gradient-based method for generating highly effective and universal prompt injection data, even in the face of defensive measures. With only five training samples (0.3% relative to the test data), our attack can achieve superior performance compared with baselines. Our findings emphasize the importance of gradient-based testing, which can avoid overestimation of robustness, especially for defense mechanisms.

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Syntology Ran 7 of 10 code samples harvested from 1 repository linked to this paper; 3 have no recorded run. Of those that ran: 2 ran · our draft was wrong; 5 ran with no contract checked.

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sheltonliu-n/universal-prompt-injection officialmentioned in papermentioned on GitHubpytorchMIT report

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2ran · our draft was wrong
5ran
3unverified

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check_for_attack_success sheltonliu-n/universal-prompt-injection/universal_prompt_injection.py official repository ran · our draft was wrong MIT (permissive) · 7a1925d40005947b · report
generate sheltonliu-n/universal-prompt-injection/universal_prompt_injection.py official repository ran · our draft was wrong MIT (permissive) · c0332de7e8c09ed4 · report
generate_pattern sheltonliu-n/universal-prompt-injection/universal_prompt_injection.py official repository ran fingerprinted MIT (permissive) · b75ce23199955ac4 · report
modify_sys_prompts sheltonliu-n/universal-prompt-injection/utils/string_utils.py official repository ran MIT (permissive) · 5234b2286e5ed655 · report
query_keyword sheltonliu-n/universal-prompt-injection/get_responses_universal.py official repository ran MIT (permissive) · 552d5602e36e866c · report
query_target sheltonliu-n/universal-prompt-injection/check_answers.py official repository ran fingerprinted MIT (permissive) · a505da2807081d09 · report
query_target sheltonliu-n/universal-prompt-injection/utils/string_utils.py official repository ran MIT (permissive) · e4d56bdd1dbd8b1c · report
get_embedding_matrix sheltonliu-n/universal-prompt-injection/utils/opt_utils.py official repository unverified MIT (permissive) · 688aaeba506e3329 · report
get_embeddings sheltonliu-n/universal-prompt-injection/utils/opt_utils.py official repository unverified MIT (permissive) · f556dda0785f3c77 · report
token_gradients sheltonliu-n/universal-prompt-injection/utils/opt_utils.py official repository unverified MIT (permissive) · 76ca4b8b6f0c1fe9 · report

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