# BACKDOORL: Backdoor Attack against Competitive Reinforcement Learning

arXiv: https://arxiv.org/abs/2105.00579 · HTML: https://mlsanity.com/paper/2105.00579/

## Key facts

- Cited by 68 papers in the map (data through 14 Oct 2026).
- Builds on 21 of its 46 references that are in the map.
- First posted on arXiv 2 May 2021.

## Builds on (most cited first, 21 of 21)

- [CARLA: An Open Urban Driving Simulator](https://mlsanity.com/paper/1711.03938/) (2017)
- [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)
- [Fine-Pruning: Defending Against Backdooring Attacks on Deep Neural Networks](https://mlsanity.com/paper/1805.12185/) (2018)
- [Detecting Backdoor Attacks on Deep Neural Networks by Activation Clustering](https://mlsanity.com/paper/1811.03728/) (2018)
- [Hidden Trigger Backdoor Attacks](https://mlsanity.com/paper/1910.00033/) (2019)
- [Analyzing Federated Learning through an Adversarial Lens](https://mlsanity.com/paper/1811.12470/) (2018)
- [Adversarial Attacks on Neural Network Policies](https://mlsanity.com/paper/1702.02284/) (2017)
- [Safe, Multi-Agent, Reinforcement Learning for Autonomous Driving](https://mlsanity.com/paper/1610.03295/) (2016)
- [Attack of the Tails: Yes, You Really Can Backdoor Federated Learning](https://mlsanity.com/paper/2007.05084/) (2020)
- [Label-Consistent Backdoor Attacks](https://mlsanity.com/paper/1912.02771/) (2019)
- [Can You Really Backdoor Federated Learning?](https://mlsanity.com/paper/1911.07963/) (2019)
- [Adversarial Policies: Attacking Deep Reinforcement Learning](https://mlsanity.com/paper/1905.10615/) (2019)
- [Tactics of Adversarial Attack on Deep Reinforcement Learning Agents](https://mlsanity.com/paper/1703.06748/) (2017)
- [TABOR: A Highly Accurate Approach to Inspecting and Restoring Trojan Backdoors in AI Systems](https://mlsanity.com/paper/1908.01763/) (2019)
- [Emergent Complexity via Multi-Agent Competition](https://mlsanity.com/paper/1710.03748/) (2017)
- [Gotta Catch 'Em All: Using Honeypots to Catch Adversarial Attacks on Neural Networks](https://mlsanity.com/paper/1904.08554/) (2019)
- [Stop-and-Go: Exploring Backdoor Attacks on Deep Reinforcement Learning-based Traffic Congestion Control Systems](https://mlsanity.com/paper/2003.07859/) (2020)
- [BAAAN: Backdoor Attacks Against Autoencoder and GAN-Based Machine Learning Models](https://mlsanity.com/paper/2010.03007/) (2020)
- [Design of intentional backdoors in sequential models](https://mlsanity.com/paper/1902.09972/) (2019)
- [Don't Trigger Me! A Triggerless Backdoor Attack Against Deep Neural Networks](https://mlsanity.com/paper/2010.03282/) (2020)

## Built on by (most cited first, 30 of 68)

- [Watch Out for Your Agents! Investigating Backdoor Threats to LLM-Based Agents](https://mlsanity.com/paper/2402.11208/) (2024)
- [Personalization as a Shortcut for Few-Shot Backdoor Attack against Text-to-Image Diffusion Models](https://mlsanity.com/paper/2305.10701/) (2023)
- [Test-Time Backdoor Attacks on Multimodal Large Language Models](https://mlsanity.com/paper/2402.08577/) (2024)
- [Rethinking the Reverse-engineering of Trojan Triggers](https://mlsanity.com/paper/2210.15127/) (2022)
- [Training with More Confidence: Mitigating Injected and Natural Backdoors During Training](https://mlsanity.com/paper/2202.06382/) (2022)
- [Few-Shot Backdoor Attacks on Visual Object Tracking](https://mlsanity.com/paper/2201.13178/) (2022)
- [BadMerging: Backdoor Attacks Against Model Merging](https://mlsanity.com/paper/2408.07362/) (2024)
- [Physical Backdoor Attacks to Lane Detection Systems in Autonomous Driving](https://mlsanity.com/paper/2203.00858/) (2022)
- [Elijah: Eliminating Backdoors Injected in Diffusion Models via Distribution Shift](https://mlsanity.com/paper/2312.00050/) (2023)
- [BadRL: Sparse Targeted Backdoor Attack Against Reinforcement Learning](https://mlsanity.com/paper/2312.12585/) (2023)
- [Imperceptible Backdoor Attack: From Input Space to Feature Representation](https://mlsanity.com/paper/2205.03190/) (2022)
- [COPA: Certifying Robust Policies for Offline Reinforcement Learning against Poisoning Attacks](https://mlsanity.com/paper/2203.08398/) (2022)
- [BAFFLE: Hiding Backdoors in Offline Reinforcement Learning Datasets](https://mlsanity.com/paper/2210.04688/) (2022)
- [PolicyCleanse: Backdoor Detection and Mitigation in Reinforcement Learning](https://mlsanity.com/paper/2202.03609/) (2022)
- [SleeperNets: Universal Backdoor Poisoning Attacks Against Reinforcement Learning Agents](https://mlsanity.com/paper/2405.20539/) (2024)
- [Provable Defense against Backdoor Policies in Reinforcement Learning](https://mlsanity.com/paper/2211.10530/) (2022)
- [Attacking Cooperative Multi-Agent Reinforcement Learning by Adversarial Minority Influence](https://mlsanity.com/paper/2302.03322/) (2023)
- [A Temporal-Pattern Backdoor Attack to Deep Reinforcement Learning](https://mlsanity.com/paper/2205.02589/) (2022)
- [Adversarial Cheap Talk](https://mlsanity.com/paper/2211.11030/) (2022)
- [Implicit Poisoning Attacks in Two-Agent Reinforcement Learning: Adversarial Policies for Training-Time Attacks](https://mlsanity.com/paper/2302.13851/) (2023)
- [Seven Security Challenges in Cross-domain Multi-agent LLM Systems](https://mlsanity.com/paper/2505.23847/) (2025)
- [ORL-AUDITOR: Dataset Auditing in Offline Deep Reinforcement Learning](https://mlsanity.com/paper/2309.03081/) (2023)
- [Efficient Adversarial Attacks on Online Multi-agent Reinforcement Learning](https://mlsanity.com/paper/2307.07670/) (2023)
- [State Backdoor: Towards Stealthy Real-world Poisoning Attack on Vision-Language-Action Model in State Space](https://mlsanity.com/paper/2601.04266/) (2026)
- [Adversarial Inception Backdoor Attacks against Reinforcement Learning](https://mlsanity.com/paper/2410.13995/) (2024)
- [SUB-PLAY: Adversarial Policies against Partially Observed Multi-Agent Reinforcement Learning Systems](https://mlsanity.com/paper/2402.03741/) (2024)
- [Data Free Backdoor Attacks](https://mlsanity.com/paper/2412.06219/) (2024)
- [BLAST: A Stealthy Backdoor Leverage Attack against Cooperative Multi-Agent Deep Reinforcement Learning based Systems](https://mlsanity.com/paper/2501.01593/) (2025)
- [Cooperative Backdoor Attack in Decentralized Reinforcement Learning with Theoretical Guarantee](https://mlsanity.com/paper/2405.15245/) (2024)
- [A Spatiotemporal Stealthy Backdoor Attack against Cooperative Multi-Agent Deep Reinforcement Learning](https://mlsanity.com/paper/2409.07775/) (2024)

## Abstract (arXiv)

Recent research has confirmed the feasibility of backdoor attacks in deep reinforcement learning (RL) systems. However, the existing attacks require the ability to arbitrarily modify an agent's observation, constraining the application scope to simple RL systems such as Atari games. In this paper, we migrate backdoor attacks to more complex RL systems involving multiple agents and explore the possibility of triggering the backdoor without directly manipulating the agent's observation. As a proof of concept, we demonstrate that an adversary agent can trigger the backdoor of the victim agent with its own action in two-player competitive RL systems. We prototype and evaluate BACKDOORL in four competitive environments. The results show that when the backdoor is activated, the winning rate of the victim drops by 17% to 37% compared to when not activated.
