# Stealthy Backdoors as Compression Artifacts

arXiv: https://arxiv.org/abs/2104.15129 · HTML: https://mlsanity.com/paper/2104.15129/

## Key facts

- Cited by 18 papers in the map (data through 14 Oct 2026).
- Builds on 45 of its 70 references that are in the map.
- First posted on arXiv 30 Apr 2021.

## Builds on (most cited first, 30 of 45)

- [Deep Residual Learning for Image Recognition](https://mlsanity.com/paper/1512.03385/) (2015)
- [BERT: Pre-training of Deep Bidirectional Transformers for Language Understanding](https://mlsanity.com/paper/1810.04805/) (2018)
- [Language Models are Few-Shot Learners](https://mlsanity.com/paper/2005.14165/) (2020)
- [PyTorch: An Imperative Style, High-Performance Deep Learning Library](https://mlsanity.com/paper/1912.01703/) (2019)
- [Very Deep Convolutional Networks for Large-Scale Image Recognition](https://mlsanity.com/paper/1409.1556/) (2014)
- [Distilling the Knowledge in a Neural Network](https://mlsanity.com/paper/1503.02531/) (2015)
- [Densely Connected Convolutional Networks](https://mlsanity.com/paper/1608.06993/) (2016)
- [MobileNets: Efficient Convolutional Neural Networks for Mobile Vision Applications](https://mlsanity.com/paper/1704.04861/) (2017)
- [Estimating or Propagating Gradients Through Stochastic Neurons for Conditional Computation](https://mlsanity.com/paper/1308.3432/) (2013)
- [Learning both Weights and Connections for Efficient Neural Networks](https://mlsanity.com/paper/1506.02626/) (2015)
- [Quantization and Training of Neural Networks for Efficient Integer-Arithmetic-Only Inference](https://mlsanity.com/paper/1712.05877/) (2017)
- [Self-training with Noisy Student improves ImageNet classification](https://mlsanity.com/paper/1911.04252/) (2019)
- [CodeBERT: A Pre-Trained Model for Programming and Natural Languages](https://mlsanity.com/paper/2002.08155/) (2020)
- [Pruning Filters for Efficient ConvNets](https://mlsanity.com/paper/1608.08710/) (2016)
- [BadNets: Identifying Vulnerabilities in the Machine Learning Model Supply Chain](https://mlsanity.com/paper/1708.06733/) (2017)
- [Targeted Backdoor Attacks on Deep Learning Systems Using Data Poisoning](https://mlsanity.com/paper/1712.05526/) (2017)
- [Big Transfer (BiT): General Visual Representation Learning](https://mlsanity.com/paper/1912.11370/) (2019)
- [Learning Structured Sparsity in Deep Neural Networks](https://mlsanity.com/paper/1608.03665/) (2016)
- [Quantizing deep convolutional networks for efficient inference: A whitepaper](https://mlsanity.com/paper/1806.08342/) (2018)
- [STRIP: A Defence Against Trojan Attacks on Deep Neural Networks](https://mlsanity.com/paper/1902.06531/) (2019)
- [AMC: AutoML for Model Compression and Acceleration on Mobile Devices](https://mlsanity.com/paper/1802.03494/) (2018)
- [Filter Pruning via Geometric Median for Deep Convolutional Neural Networks Acceleration](https://mlsanity.com/paper/1811.00250/) (2018)
- [Dynamic Network Surgery for Efficient DNNs](https://mlsanity.com/paper/1608.04493/) (2016)
- [Learning to Prune Deep Neural Networks via Layer-wise Optimal Brain Surgeon](https://mlsanity.com/paper/1705.07565/) (2017)
- [Quantized Convolutional Neural Networks for Mobile Devices](https://mlsanity.com/paper/1512.06473/) (2015)
- [Detecting AI Trojans Using Meta Neural Analysis](https://mlsanity.com/paper/1910.03137/) (2019)
- [Compressing Deep Convolutional Networks using Vector Quantization](https://mlsanity.com/paper/1412.6115/) (2014)
- [Blind Backdoors in Deep Learning Models](https://mlsanity.com/paper/2005.03823/) (2020)
- [Machine Learning Models that Remember Too Much](https://mlsanity.com/paper/1709.07886/) (2017)
- [Dynamic Backdoor Attacks Against Machine Learning Models](https://mlsanity.com/paper/2003.03675/) (2020)

## Built on by (most cited first, 18 of 18)

- [Exploiting LLM Quantization](https://mlsanity.com/paper/2405.18137/) (2024)
- [Quantization Backdoors to Deep Learning Commercial Frameworks](https://mlsanity.com/paper/2108.09187/) (2021)
- [Attacks in Adversarial Machine Learning: A Systematic Survey from the Life-cycle Perspective](https://mlsanity.com/paper/2302.09457/) (2023)
- [Nearest is Not Dearest: Towards Practical Defense against Quantization-conditioned Backdoor Attacks](https://mlsanity.com/paper/2405.12725/) (2024)
- [Mind Your Heart: Stealthy Backdoor Attack on Dynamic Deep Neural Network in Edge Computing](https://mlsanity.com/paper/2212.11751/) (2022)
- [PublicCheck: Public Integrity Verification for Services of Run-time Deep Models](https://mlsanity.com/paper/2203.10902/) (2022)
- [Taught Well Learned Ill: Towards Distillation-conditional Backdoor Attack](https://mlsanity.com/paper/2509.23871/) (2025)
- [RIBAC: Towards Robust and Imperceptible Backdoor Attack against Compact DNN](https://mlsanity.com/paper/2208.10608/) (2022)
- [NTD: Non-Transferability Enabled Backdoor Detection](https://mlsanity.com/paper/2111.11157/) (2021)
- [Rounding-Guided Backdoor Injection in Deep Learning Model Quantization](https://mlsanity.com/paper/2510.09647/) (2025)
- [You Never Know: Quantization Induces Inconsistent Biases in Vision-Language Foundation Models](https://mlsanity.com/paper/2410.20265/) (2024)
- [FloatDoor: Platform-Triggered Backdoors in LLMs](https://mlsanity.com/paper/2606.19535/) (2026)
- [Theory of Minimal Weight Perturbations in Deep Networks and its Applications for Low-Rank Activated Backdoor Attacks](https://mlsanity.com/paper/2601.16880/) (2026)
- [Surveying the Operational Cybersecurity and Supply Chain Threat Landscape when Developing and Deploying AI Systems](https://mlsanity.com/paper/2508.20307/) (2025)
- [HAMLOCK: HArdware-Model LOgically Combined attacK](https://mlsanity.com/paper/2510.19145/) (2025)
- [Quantization Blindspots: How Model Compression Breaks Backdoor Defenses](https://mlsanity.com/paper/2512.06243/) (2025)
- [FlipGuard: Defending Large Language Models Against Quantization-Conditioned Backdoor Attacks](https://mlsanity.com/paper/2606.28962/) (2026)
- [Towards Merging-conditional Backdoor Unalignment against Large Language Models](https://mlsanity.com/paper/2610.14701/) (2026)

## Abstract (arXiv)

In a backdoor attack on a machine learning model, an adversary produces a model that performs well on normal inputs but outputs targeted misclassifications on inputs containing a small trigger pattern. Model compression is a widely-used approach for reducing the size of deep learning models without much accuracy loss, enabling resource-hungry models to be compressed for use on resource-constrained devices. In this paper, we study the risk that model compression could provide an opportunity for adversaries to inject stealthy backdoors. We design stealthy backdoor attacks such that the full-sized model released by adversaries appears to be free from backdoors (even when tested using state-of-the-art techniques), but when the model is compressed it exhibits highly effective backdoors. We show this can be done for two common model compression techniques -- model pruning and model quantization. Our findings demonstrate how an adversary may be able to hide a backdoor as a compression artifact, and show the importance of performing security tests on the models that will actually be deployed not their precompressed version.
