Cited by 667Adversarial Robustness in Machine LearningSecurity and Verification in ComputingWeb Application Security Vulnerabilities

The DOI matches its Crossref record; 40 of the 40 references it cites were found in a registry or an index; 22 of the 36 sources its claims cite were checked for support.

Not What You've Signed Up For: Compromising Real-World LLM-Integrated Applications with Indirect Prompt Injection

Open access
Greshake, Kai, Abdelnabi, Sahar, Mishra, Shailesh, Endres, Christoph, Holz, Thorsten, Fritz, Mario·2023·Proceedings of the 16th ACM Workshop on Artificial Intelligence and Security

Abstract

Large Language Models (LLMs) are increasingly being integrated into applications, with versatile functionalities that can be easily modulated via natural language prompts. So far, it was assumed that the user is directly prompting the LLM. But, what if it is not the user prompting? We show that LLM-Integrated Applications blur the line between data and instructions and reveal several new attack vectors, using Indirect Prompt Injection, that enable adversaries to remotely (i.e., without a direct interface) exploit LLM-integrated applications by strategically injecting prompts into data likely to be retrieved at inference time. We derive a comprehensive taxonomy from a computer security perspective to broadly investigate impacts and vulnerabilities, including data theft, worming, information ecosystem contamination, and other novel security risks. We then demonstrate the practical viability of our attacks against both real-world systems, such as Bing Chat and code-completion engines, and GPT-4 synthetic applications. We show how processing retrieved prompts can act as arbitrary code execution, manipulate the application's functionality, and control how and if other APIs are called. Despite the increasing reliance on LLMs, effective mitigations of these emerging threats are lacking. By raising awareness of these vulnerabilities, we aim to promote the safe and responsible deployment of these powerful models and the development of robust defenses that protect users from potential attacks.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

The paper introduces indirect prompt injection, where adversaries place prompts in data that LLM-integrated applications retrieve, allowing remote manipulation without directly prompting the model. It develops a security taxonomy and demonstrates practical attacks against Bing Chat, GitHub Copilot, and synthetic GPT-4/text-davinci-003 applications, covering data theft, fraud, malware, intrusion, content manipulation, and availability disruption.

Key findings

  • Retrieved content can function like instructions, letting third-party data steer model behavior; the authors report that all described proof-of-concept demonstrations triggered the intended behavior.
  • Attacks can persuade users to reveal personal information, exfiltrate data through side effects such as URL retrieval, distribute phishing or malware links, and turn prompts into self-propagating “AI malware” that reads address books and forwards injections by email.
  • Intrusion demonstrations include remote control by fetching new commands from an attacker-controlled server, persistence through memory reinfection, and contamination of code-completion suggestions; content-manipulation demonstrations include wrong summaries, source blocking, disinformation, and undisclosed advertisements.
  • Hidden-injection methods include multi-stage payload retrieval and a Base64-encoded prompt that worked on Bing Chat; the model also sometimes issued follow-up search queries that reinforced the injected prompt.

Methods

  • The authors build a threat model and taxonomy from a computer security perspective, classifying injection delivery as passive retrieval, active delivery, user-driven, or hidden, and mapping threats to affected parties.
  • Synthetic applications used OpenAI APIs: text-davinci-003 with LangChain and ReAct prompting, and GPT-4 in chat format, with mock tools for search, viewing pages, retrieving URLs, reading/sending email, reading an address book, and memory; all interfaces returned prepared content, no real systems were contacted, and attacks ran at sampling temperature 0.
  • Real-world black-box tests targeted Bing Chat, including its Edge sidebar reading local HTML files, and GitHub Copilot/Codex for code-completion manipulation; prompts were manually written, and local HTML was used to avoid public injections.

Limitations

  • The paper states that attacks were tested on local HTML files rather than public in-the-wild injections, that Microsoft 365 Copilot and ChatGPT plugins were inaccessible, that success rates are hard to quantify in dynamic interactive sessions, that believability was assessed qualitatively, and that exact reproducibility is difficult in black-box systems.
  • The text also makes evident that code-completion injections were highly context-sensitive and lost efficacy in larger packages or projects, and that some availability attacks, such as inhibiting API calls, succeeded only inconsistently.
  • The authors note that user studies are needed to quantify deception potential across different attacks and setups.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1145/3605764.3623985

Cites

40 of 40 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

50 Own interpretation · 28 Own result · 20 No basis given · 9 Couldn’t confirm · 7 Sources not found · 6 Partly supported · 5 No full text of the sources · 3 Supported · 3 Own method · 1 Not checked yet · accuracy not yet measured

Show all 51 claims

  • Probably not a substantial claim. 51
  • It may state two separate claims as one. 45
81 of 81
  • The authors state this as an assumption.

    The attacker has the ability to remotely poison the potential input to the model at inference time.

    “Assumptions.The attacks only assume the ability of the attacker to remotely poison the potential input to the model at inference time.”
  • The paper relies on this without support.

    The synthetic applications provide a close mock-up of the intended functionalities of current systems.

    “These applications provide a close mock-up of the intended functionalities of current systems and thus can be used for controlled testing.”
  • The authors state this as an assumption.

    The model itself generates the search query (i.e., the arguments to APIs).

    “This attack is based on the assumption that the model itself generates the search query (i.e., the arguments to APIs).”
  • The paper relies on this without support.

    Bing Chat cannot repeat the <| endoftext|> token or finish sentences when this token appears in the middle.

    “Users reported that Bing Chat cannot repeat the <| endoftext|> token or finish sentences when this token appears in the middle.”
  • The paper relies on this without support.

    The algorithms that compose the context window are proprietary.

    “Because the algorithms that compose the context window are proprietary, more research is needed to determine the feasibility of this new attack.”
5 of 5

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

1 of 1

Citations

Cites

Show all 11 references

Research works printed but not linked: 5

  1. Nicholas Carlini, Milad Nasr, Christopher A Choquette-Choo, Matthew Jagielski, Irena Gao, Anas Awadalla, Pang Wei Koh, Daphne Ippolito, Katherine Lee, Florian Tramer, et al. 2023. Are aligned neural networks adversarially aligned? arXiv (2023).
  2. Clarence Chio and David Freeman. 2018. Machine learning and security. "O'Reilly Media, Inc.".
  3. Noah Goodman Jesse Mu, Xiang Lisa Li. 2023. Learning to Compress Prompts with Gist Tokens. arXiv (2023).
  4. Pan Lu, Baolin Peng, Hao Cheng, Michel Galley, Kai-Wei Chang, Ying Nian Wu, Song-Chun Zhu, and Jianfeng Gao. 2023. Chameleon: Plug-and-play compositional reasoning with large language models. arXiv (2023).
  5. Shunyu Yao Jeffrey Zhao Dian Yu Izhak Shafran Karthik R Narasimhan and Yuan Cao. 2023. ReAct: Synergizing Reasoning and Acting in Language Models. In ICLR.

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Metadata

Authors
Greshake, K., Abdelnabi, S., Mishra, S., Endres, C., Holz, T., & Fritz, M.
Affiliations
  • Saarland University (DE)
  • Helmholtz Center for Information Security (DE)
  • Université franco-allemande (DE)
Venue
Proceedings of the 16th ACM Workshop on Artificial Intelligence and Security
Publisher
ACM
Published
2023-11-26
Pages
79-90
OpenAlex
W4388886073
Cited by
667
References
11
Citations by year
2026: 416 · 2025: 153 · 2024: 86 · 2023: 12
FWCI
117.91
Type
conference paper
Language
en
Open access
Locations
ACM Workshop on Artificial Intelligence and Security (AISec) (publishedVersion)
Funders
European Union (101070617)
Topics
  • Physical Sciences › Computer Science › Artificial Intelligence › Adversarial Robustness in Machine Learning
  • Physical Sciences › Computer Science › Hardware and Architecture › Security and Verification in Computing
  • Physical Sciences › Computer Science › Information Systems › Web Application Security Vulnerabilities
Keywords
indirect prompt injection, large language models, prompt injection, data theft, arbitrary code execution, attack taxonomy, Bing Chat, security risk mitigation

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