Be Careful about Poisoned Word Embeddings: Exploring the Vulnerability of the Embedding Layers in NLP Models
On the map: LLM safety and security → Backdoor and data poisoning attacks
Abstract (arXiv)
Recent studies have revealed a security threat to natural language processing (NLP) models, called the Backdoor Attack. Victim models can maintain competitive performance on clean samples while behaving abnormally on samples with a specific trigger word inserted. Previous backdoor attacking methods usually assume that attackers have a certain degree of data knowledge, either the dataset which users would use or proxy datasets for a similar task, for implementing the data poisoning procedure. However, in this paper, we find that it is possible to hack the model in a data-free way by modifying one single word embedding vector, with almost no accuracy sacrificed on clean samples. Experimental results on sentiment analysis and sentence-pair classification tasks show that our method is more efficient and stealthier. We hope this work can raise the awareness of such a critical security risk hidden in the embedding layers of NLP models. Our code is available at https://github.com/lancopku/Embedding-Poisoning.
Key facts. Cited by 96 papers in the map (data through 7 Oct 2026). Placed in Backdoor and data poisoning attacks, one of 12 directions in LLM safety and security. Builds on 23 of its 38 references that are in the map. First posted on arXiv 29 Mar 2021.
Builds on
23 of 38 references.
References · 23
- 2017Attention Is All You Needcited by 59,932
- 2015Deep Residual Learning for Image Recognitioncited by 51,809
- 2018BERT: Pre-training of Deep Bidirectional Transformers for Language Understandingcited by 40,204
- 2014Adam: A Method for Stochastic Optimizationcited by 36,960
- 2019RoBERTa: A Robustly Optimized BERT Pretraining Approachcited by 13,266
- 2016SQuAD: 100,000+ Questions for Machine Comprehension of Textcited by 4,115
- 2016Pointer Sentinel Mixture Modelscited by 2,992
- 2014Sequence to Sequence Learning with Neural Networkscited by 2,974
- 2019XLNet: Generalized Autoregressive Pretraining for Language Understandingcited by 2,801
- 2017BadNets: Identifying Vulnerabilities in the Machine Learning Model Supply Chaincited by 1,052
- 2019Hidden Trigger Backdoor Attackscited by 359
- 2020Reflection Backdoor: A Natural Backdoor Attack on Deep Neural Networkscited by 341
11 more
- 2020Weight Poisoning Attacks on Pre-trained Modelscited by 318
- 2020Input-Aware Dynamic Backdoor Attackcited by 304
- 2019A backdoor attack against LSTM-based text classification systemscited by 214
- 2019Zero-Shot Knowledge Distillation in Deep Networkscited by 119
- 2020Practical Detection of Trojan Neural Networks: Data-Limited and Data-Free Casescited by 93
- 2020Trojaning Language Models for Fun and Profitcited by 80
- 2020Rethinking the Trigger of Backdoor Attackcited by 76
- 2020Can Adversarial Weight Perturbations Inject Neural Backdoors?cited by 51
- 2019NeuronInspect: Detecting Backdoors in Neural Networks via Output Explanationscited by 49
- 2020Poison Attacks against Text Datasets with Conditional Adversarially Regularized Autoencodercited by 27
- 2020Humpty Dumpty: Controlling Word Meanings via Corpus Poisoningcited by 17
Built on by
Citing papers per year: 2021: 8; 2022: 17; 2023: 23; 2024: 32; 2025: 12; 2026: 4.
96 papers.
Sort:
By area:
- 2023Poisoning Language Models During Instruction Tuningcited by 254
- 2023Large Language Model Alignment: A Surveycited by 241
- 2024Security and Privacy Challenges of Large Language Models: A Surveycited by 179
- 2024Watch Out for Your Agents! Investigating Backdoor Threats to LLM-Based Agentscited by 135
- 2023Universal Jailbreak Backdoors from Poisoned Human Feedbackcited by 120
- 2021Backdoor Attacks on Pre-trained Models by Layerwise Weight Poisoningcited by 103
- 2021RAP: Robustness-Aware Perturbations for Defending against Backdoor Attacks on NLP Modelscited by 97
- 2023A Survey of Safety and Trustworthiness of Large Language Models through the Lens of Verification and Validationcited by 91
- 2021BadPre: Task-agnostic Backdoor Attacks to Pre-trained NLP Foundation Modelscited by 76
- 2022A Unified Evaluation of Textual Backdoor Learning: Frameworks and Benchmarkscited by 70
- 2021Spinning Language Models: Risks of Propaganda-As-A-Service and Countermeasurescited by 69
- 2024Instructional Fingerprinting of Large Language Modelscited by 64
38 more
- 2023Composite Backdoor Attacks Against Large Language Modelscited by 63
- 2021Triggerless Backdoor Attack for NLP Tasks with Clean Labelscited by 61
- 2023Are You Copying My Model? Protecting the Copyright of Large Language Models for EaaS via Backdoor Watermarkcited by 61
- 2022BadPrompt: Backdoor Attacks on Continuous Promptscited by 59
- 2022Fine-mixing: Mitigating Backdoors in Fine-tuned Language Modelscited by 50
- 2023Privacy in Large Language Models: Attacks, Defenses and Future Directionscited by 48
- 2022A Study of the Attention Abnormality in Trojaned BERTscited by 47
- 2022BITE: Textual Backdoor Attacks with Iterative Trigger Injectioncited by 47
- 2024Persistent Pre-Training Poisoning of LLMscited by 46
- 2022Constrained Optimization with Dynamic Bound-scaling for Effective NLPBackdoor Defensecited by 44
- 2022Watermarking Pre-trained Language Models with Backdooringcited by 44
- 2023UNICORN: A Unified Backdoor Trigger Inversion Frameworkcited by 44
- 2024Operationalizing a Threat Model for Red-Teaming Large Language Models (LLMs)cited by 44
- 2022Rethinking the Reverse-engineering of Trojan Triggerscited by 37
- 2024Securing Large Language Models: Threats, Vulnerabilities and Responsible Practicescited by 36
- 2024A Survey of Recent Backdoor Attacks and Defenses in Large Language Modelscited by 36
- 2023Defending Pre-trained Language Models as Few-shot Learners against Backdoor Attackscited by 32
- 2023Attention-Enhancing Backdoor Attacks Against BERT-based Modelscited by 32
- 2024Mitigating Fine-tuning based Jailbreak Attack with Backdoor Enhanced Safety Alignmentcited by 31
- 2021Defending Against Backdoor Attacks in Natural Language Generationcited by 30
- 2023ChatGPT as an Attack Tool: Stealthy Textual Backdoor Attack via Blackbox Generative Model Triggercited by 29
- 2023Training-free Lexical Backdoor Attacks on Language Modelscited by 27
- 2024Competition Report: Finding Universal Jailbreak Backdoors in Aligned LLMscited by 27
- 2023From Shortcuts to Triggers: Backdoor Defense with Denoised PoEcited by 26
- 2023Defending against Insertion-based Textual Backdoor Attacks via Attributioncited by 24
- 2024Task-Agnostic Detector for Insertion-Based Backdoor Attackscited by 23
- 2025DemonAgent: Dynamically Encrypted Multi-Backdoor Implantation Attack on LLM-based Agentcited by 23
- 2021How to Inject Backdoors with Better Consistency: Logit Anchoring on Clean Datacited by 22
- 2024BadActs: A Universal Backdoor Defense in the Activation Spacecited by 19
- 2022Expose Backdoors on the Way: A Feature-Based Efficient Defense against Textual Backdoor Attackscited by 18
- 2024Double-I Watermark: Protecting Model Copyright for LLM Fine-tuningcited by 18
- 2023ParaFuzz: An Interpretability-Driven Technique for Detecting Poisoned Samples in NLPcited by 16
- 2023TextGuard: Provable Defense against Backdoor Attacks on Text Classificationcited by 14
- 2024Decoding the AI Pen: Techniques and Challenges in Detecting AI-Generated Textcited by 14
- 2022A Survey on Backdoor Attack and Defense in Natural Language Processingcited by 13
- 2024Cognitive Overload Attack:Prompt Injection for Long Contextcited by 13
- 2023Watermarking Vision-Language Pre-trained Models for Multi-modal Embedding as a Servicecited by 11
- 2024Exploring Backdoor Vulnerabilities of Chat Modelscited by 11
50 most cited of 96 All 96 (JSON)
- 2026When Explanations Betray Backdoors: Black-Box Auditing for Language Model Classifiers12 Aug 2026
- 2026DocRetriever: A Plug-and-Play Framework for Multimodal Document Retrieval with Comprehensive Benchmark28 May 2026
- 2026Position: Retire the "Positive Backdoor" Label -- Secret Alignment Requires Strict and Systematic Evaluation27 May 2026
- 2026Re-Triggering Safeguards within LLMs for Jailbreak Detection11 May 2026
- 2025Unmasking Backdoors: An Explainable Defense via Gradient-Attention Anomaly Scoring for Pre-trained Language Models5 Oct 2025
- 2025Pruning Strategies for Backdoor Defense in LLMs27 Aug 2025
- 2025Strategic Sample Selection for Improved Clean-Label Backdoor Attacks in Text Classification21 Aug 2025
- 2025On The Role of Pretrained Language Models in General-Purpose Text Embeddings: A Survey28 Jul 2025
- 2025TED-LaST: Towards Robust Backdoor Defense Against Adaptive Attacks12 Jun 2025
- 2025LLM Security: Vulnerabilities, Attacks, Defenses, and Countermeasures2 May 2025
- 2025BadMoE: Backdooring Mixture-of-Experts LLMs via Optimizing Routing Triggers and Infecting Dormant Experts24 Apr 2025
- 2025The Ultimate Cookbook for Invisible Poison: Crafting Subtle Clean-Label Text Backdoors with Style Attributes24 Apr 2025
38 more
- 2025MuTRAP: Multi-trigger Trojans Attacking Robot Task Planning Systems23 Apr 2025
- 2025PoisonedParrot: Subtle Data Poisoning Attacks to Elicit Copyright-Infringing Content from Large Language Models10 Mar 2025
- 2025Char-mander Use mBackdoor! A Study of Cross-lingual Backdoor Attacks in Multilingual LLMs24 Feb 2025
- 2025DemonAgent: Dynamically Encrypted Multi-Backdoor Implantation Attack on LLM-based Agent18 Feb 2025
- 2024Cut the Deadwood Out: Backdoor Purification via Guided Module Substitution29 Dec 2024
- 2024Neutralizing Backdoors through Information Conflicts for Large Language Models27 Nov 2024
- 2024Persistent Pre-Training Poisoning of LLMs17 Oct 2024
- 2024Cognitive Overload Attack:Prompt Injection for Long Context15 Oct 2024
- 2024Data-centric NLP Backdoor Defense from the Lens of Memorization21 Sep 2024
- 2024Exploiting the Vulnerability of Large Language Models via Defense-Aware Architectural Backdoor3 Sep 2024
- 2024Large Language Models are Good Attackers: Efficient and Stealthy Textual Backdoor Attacks21 Aug 2024
- 2024MEGen: Generative Backdoor into Large Language Models via Model Editing20 Aug 2024
- 2024Can LLMs be Fooled? Investigating Vulnerabilities in LLMs30 Jul 2024
- 2024Operationalizing a Threat Model for Red-Teaming Large Language Models (LLMs)20 Jul 2024
- 2024R-SFLLM: Jamming Resilient Framework for Split Federated Learning with Large Language Models16 Jul 2024
- 2024SOS! Soft Prompt Attack Against Open-Source Large Language Models3 Jul 2024
- 2024Stealth edits to large language models18 Jun 2024
- 2024A Survey of Recent Backdoor Attacks and Defenses in Large Language Models10 Jun 2024
- 2024PromptFix: Few-shot Backdoor Removal via Adversarial Prompt Tuning6 Jun 2024
- 2024TrojFM: Resource-efficient Backdoor Attacks against Very Large Foundation Models27 May 2024
- 2024BadActs: A Universal Backdoor Defense in the Activation Space18 May 2024
- 2024Competition Report: Finding Universal Jailbreak Backdoors in Aligned LLMs22 Apr 2024
- 2024Exploring Backdoor Vulnerabilities of Chat Models3 Apr 2024
- 2024Two Heads are Better than One: Nested PoE for Robust Defense Against Multi-Backdoors2 Apr 2024
- 2024Shortcuts Arising from Contrast: Effective and Covert Clean-Label Attacks in Prompt-Based Learning30 Mar 2024
- 2024Task-Agnostic Detector for Insertion-Based Backdoor Attacks25 Mar 2024
- 2024Securing Large Language Models: Threats, Vulnerabilities and Responsible Practices19 Mar 2024
- 2024Decoding the AI Pen: Techniques and Challenges in Detecting AI-Generated Text9 Mar 2024
- 2024Can Distillation Mitigate Backdoor Attacks in Pre-trained Encoders?6 Mar 2024
- 2024SynGhost: Invisible and Universal Task-agnostic Backdoor Attack via Syntactic Transfer29 Feb 2024
- 2024Mitigating Fine-tuning based Jailbreak Attack with Backdoor Enhanced Safety Alignment22 Feb 2024
- 2024Double-I Watermark: Protecting Model Copyright for LLM Fine-tuning22 Feb 2024
- 2024Watch Out for Your Agents! Investigating Backdoor Threats to LLM-Based Agents17 Feb 2024
- 2024Manipulating Predictions over Discrete Inputs in Machine Teaching31 Jan 2024
- 2024Security and Privacy Challenges of Large Language Models: A Survey30 Jan 2024
- 2024Instructional Fingerprinting of Large Language Models21 Jan 2024
- 2023Punctuation Matters! Stealthy Backdoor Attack for Language Models26 Dec 2023
- 2023Universal Jailbreak Backdoors from Poisoned Human Feedback24 Nov 2023
50 newest of 96 All 96 (JSON)
- 2024Security and Privacy Challenges of Large Language Models: A Surveycited by 179
- 2021RAP: Robustness-Aware Perturbations for Defending against Backdoor Attacks on NLP Modelscited by 97
- 2021BadPre: Task-agnostic Backdoor Attacks to Pre-trained NLP Foundation Modelscited by 76
- 2022A Unified Evaluation of Textual Backdoor Learning: Frameworks and Benchmarkscited by 70
- 2021Spinning Language Models: Risks of Propaganda-As-A-Service and Countermeasurescited by 69
- 2023Composite Backdoor Attacks Against Large Language Modelscited by 63
- 2021Triggerless Backdoor Attack for NLP Tasks with Clean Labelscited by 61
- 2023Are You Copying My Model? Protecting the Copyright of Large Language Models for EaaS via Backdoor Watermarkcited by 61
- 2022BadPrompt: Backdoor Attacks on Continuous Promptscited by 59
- 2022Fine-mixing: Mitigating Backdoors in Fine-tuned Language Modelscited by 50
- 2022BITE: Textual Backdoor Attacks with Iterative Trigger Injectioncited by 47
- 2022Constrained Optimization with Dynamic Bound-scaling for Effective NLPBackdoor Defensecited by 44
12 most cited of 56 All 56 (JSON)
- 2026When Explanations Betray Backdoors: Black-Box Auditing for Language Model Classifiers12 Aug 2026
- 2026Re-Triggering Safeguards within LLMs for Jailbreak Detection11 May 2026
- 2025Unmasking Backdoors: An Explainable Defense via Gradient-Attention Anomaly Scoring for Pre-trained Language Models5 Oct 2025
- 2025Pruning Strategies for Backdoor Defense in LLMs27 Aug 2025
- 2025Strategic Sample Selection for Improved Clean-Label Backdoor Attacks in Text Classification21 Aug 2025
- 2025The Ultimate Cookbook for Invisible Poison: Crafting Subtle Clean-Label Text Backdoors with Style Attributes24 Apr 2025
- 2025PoisonedParrot: Subtle Data Poisoning Attacks to Elicit Copyright-Infringing Content from Large Language Models10 Mar 2025
- 2025Char-mander Use mBackdoor! A Study of Cross-lingual Backdoor Attacks in Multilingual LLMs24 Feb 2025
- 2024Neutralizing Backdoors through Information Conflicts for Large Language Models27 Nov 2024
- 2024Cognitive Overload Attack:Prompt Injection for Long Context15 Oct 2024
- 2024Data-centric NLP Backdoor Defense from the Lens of Memorization21 Sep 2024
- 2024Exploiting the Vulnerability of Large Language Models via Defense-Aware Architectural Backdoor3 Sep 2024
12 newest of 56 All 56 (JSON)
- 2023Poisoning Language Models During Instruction Tuningcited by 254
- 2021Backdoor Attacks on Pre-trained Models by Layerwise Weight Poisoningcited by 103
- 2023A Survey of Safety and Trustworthiness of Large Language Models through the Lens of Verification and Validationcited by 91
- 2024Instructional Fingerprinting of Large Language Modelscited by 64
- 2023Privacy in Large Language Models: Attacks, Defenses and Future Directionscited by 48
- 2022A Study of the Attention Abnormality in Trojaned BERTscited by 47
- 2024Persistent Pre-Training Poisoning of LLMscited by 46
- 2023UNICORN: A Unified Backdoor Trigger Inversion Frameworkcited by 44
- 2024Securing Large Language Models: Threats, Vulnerabilities and Responsible Practicescited by 36
- 2024Mitigating Fine-tuning based Jailbreak Attack with Backdoor Enhanced Safety Alignmentcited by 31
- 2023From Shortcuts to Triggers: Backdoor Defense with Denoised PoEcited by 26
- 2024Task-Agnostic Detector for Insertion-Based Backdoor Attackscited by 23
12 most cited of 32 All 32 (JSON)
- 2026DocRetriever: A Plug-and-Play Framework for Multimodal Document Retrieval with Comprehensive Benchmark28 May 2026
- 2025On The Role of Pretrained Language Models in General-Purpose Text Embeddings: A Survey28 Jul 2025
- 2025TED-LaST: Towards Robust Backdoor Defense Against Adaptive Attacks12 Jun 2025
- 2025LLM Security: Vulnerabilities, Attacks, Defenses, and Countermeasures2 May 2025
- 2025MuTRAP: Multi-trigger Trojans Attacking Robot Task Planning Systems23 Apr 2025
- 2024Cut the Deadwood Out: Backdoor Purification via Guided Module Substitution29 Dec 2024
- 2024Persistent Pre-Training Poisoning of LLMs17 Oct 2024
- 2024Can LLMs be Fooled? Investigating Vulnerabilities in LLMs30 Jul 2024
- 2024R-SFLLM: Jamming Resilient Framework for Split Federated Learning with Large Language Models16 Jul 2024
- 2024Stealth edits to large language models18 Jun 2024
- 2024BadActs: A Universal Backdoor Defense in the Activation Space18 May 2024
- 2024Task-Agnostic Detector for Insertion-Based Backdoor Attacks25 Mar 2024
12 newest of 32 All 32 (JSON)