# RL-JACK: Reinforcement Learning-powered Black-box Jailbreaking Attack against LLMs

arXiv: https://arxiv.org/abs/2406.08725 · HTML: https://mlsanity.com/paper/2406.08725/

## Key facts

- Cited by 23 papers in the map (data through 14 Oct 2026).
- Placed in Safety alignment and jailbreak attacks, one of 10 directions in LLM alignment / RLHF / preference optimisation.
- Builds on 38 of its 69 references that are in the map.
- First posted on arXiv 13 Jun 2024.

## Placed in

- LLM alignment / RLHF / preference optimisation / [Safety alignment and jailbreak attacks](https://mlsanity.com/alignment/safety-alignment-and-jailbreak-attacks/)
- LLM safety and security / [Jailbreaking](https://mlsanity.com/safety/jailbreaking/)

## Builds on (most cited first, 30 of 38)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [Adam: A Method for Stochastic Optimization](https://mlsanity.com/paper/1412.6980/) (2014)
- [Language Models are Few-Shot Learners](https://mlsanity.com/paper/2005.14165/) (2020)
- [High-Resolution Image Synthesis with Latent Diffusion Models](https://mlsanity.com/paper/2112.10752/) (2021)
- [Training language models to follow instructions with human feedback](https://mlsanity.com/paper/2203.02155/) (2022)
- [Proximal Policy Optimization Algorithms](https://mlsanity.com/paper/1707.06347/) (2017)
- [Llama 2: Open Foundation and Fine-Tuned Chat Models](https://mlsanity.com/paper/2307.09288/) (2023)
- [Explaining and Harnessing Adversarial Examples](https://mlsanity.com/paper/1412.6572/) (2014)
- [Hierarchical Text-Conditional Image Generation with CLIP Latents](https://mlsanity.com/paper/2204.06125/) (2022)
- [Finetuned Language Models Are Zero-Shot Learners](https://mlsanity.com/paper/2109.01652/) (2021)
- [Asynchronous Methods for Deep Reinforcement Learning](https://mlsanity.com/paper/1602.01783/) (2016)
- [Jailbroken: How Does LLM Safety Training Fail?](https://mlsanity.com/paper/2307.02483/) (2023)
- [Rethinking the Role of Demonstrations: What Makes In-Context Learning Work?](https://mlsanity.com/paper/2202.12837/) (2022)
- [Jailbreaking Black Box Large Language Models in Twenty Queries](https://mlsanity.com/paper/2310.08419/) (2023)
- [Fine-tuning Aligned Language Models Compromises Safety, Even When Users Do Not Intend To!](https://mlsanity.com/paper/2310.03693/) (2023)
- [Red Teaming Language Models with Language Models](https://mlsanity.com/paper/2202.03286/) (2022)
- [Tree of Attacks: Jailbreaking Black-Box LLMs Automatically](https://mlsanity.com/paper/2312.02119/) (2023)
- [Baseline Defenses for Adversarial Attacks Against Aligned Language Models](https://mlsanity.com/paper/2309.00614/) (2023)
- [How Johnny Can Persuade LLMs to Jailbreak Them: Rethinking Persuasion to Challenge AI Safety by Humanizing LLMs](https://mlsanity.com/paper/2401.06373/) (2024)
- [GPTFUZZER: Red Teaming Large Language Models with Auto-Generated Jailbreak Prompts](https://mlsanity.com/paper/2309.10253/) (2023)
- [DecodingTrust: A Comprehensive Assessment of Trustworthiness in GPT Models](https://mlsanity.com/paper/2306.11698/) (2023)
- [Jailbreaking ChatGPT via Prompt Engineering: An Empirical Study](https://mlsanity.com/paper/2305.13860/) (2023)
- [Jailbreak and Guard Aligned Language Models with Only Few In-Context Demonstrations](https://mlsanity.com/paper/2310.06387/) (2023)
- [GPT-4 Is Too Smart To Be Safe: Stealthy Chat with LLMs via Cipher](https://mlsanity.com/paper/2308.06463/) (2023)
- [DeepInception: Hypnotize Large Language Model to Be Jailbreaker](https://mlsanity.com/paper/2311.03191/) (2023)
- [A Holistic Approach to Undesired Content Detection in the Real World](https://mlsanity.com/paper/2208.03274/) (2022)
- [SafeDecoding: Defending against Jailbreak Attacks via Safety-Aware Decoding](https://mlsanity.com/paper/2402.08983/) (2024)
- [Is Reinforcement Learning (Not) for Natural Language Processing: Benchmarks, Baselines, and Building Blocks for Natural Language Policy Optimization](https://mlsanity.com/paper/2210.01241/) (2022)
- [LLM Self Defense: By Self Examination, LLMs Know They Are Being Tricked](https://mlsanity.com/paper/2308.07308/) (2023)
- [Red-Teaming Large Language Models using Chain of Utterances for Safety-Alignment](https://mlsanity.com/paper/2308.09662/) (2023)

## Built on by (most cited first, 23 of 23)

- [Frontier AI's Impact on the Cybersecurity Landscape](https://mlsanity.com/paper/2504.05408/) (2025)
- [REINFORCE Adversarial Attacks on Large Language Models: An Adaptive, Distributional, and Semantic Objective](https://mlsanity.com/paper/2502.17254/) (2025)
- [LeakAgent: RL-based Red-teaming Agent for LLM Privacy Leakage](https://mlsanity.com/paper/2412.05734/) (2024)
- [Stealthy Jailbreak Attacks on Large Language Models via Benign Data Mirroring](https://mlsanity.com/paper/2410.21083/) (2024)
- [PathSeeker: Exploring LLM Security Vulnerabilities with a Reinforcement Learning-Based Jailbreak Approach](https://mlsanity.com/paper/2409.14177/) (2024)
- [xJailbreak: Representation Space Guided Reinforcement Learning for Interpretable LLM Jailbreaking](https://mlsanity.com/paper/2501.16727/) (2025)
- [Guardians and Offenders: A Survey on Harmful Content Generation and Safety Mitigation of LLM](https://mlsanity.com/paper/2508.05775/) (2025)
- [SoK: Systematizing LLM Prompt Security: Taxonomies, Datasets, and Unified Evaluation of Attacks and Defenses](https://mlsanity.com/paper/2510.15476/) (2025)
- [VERA: Variational Inference Framework for Jailbreaking Large Language Models](https://mlsanity.com/paper/2506.22666/) (2025)
- [Temporal Logic-Based Multi-Vehicle Backdoor Attacks against Offline RL Agents in End-to-end Autonomous Driving](https://mlsanity.com/paper/2509.16950/) (2025)
- [Jailbreaking LLMs & VLMs: Mechanisms, Evaluation, and Unified Defense](https://mlsanity.com/paper/2601.03594/) (2026)
- [Formalization Driven LLM Prompt Jailbreaking via Reinforcement Learning](https://mlsanity.com/paper/2509.23558/) (2025)
- [Jailbreaking Large Language Models through Iterative Tool-Disguised Attacks via Reinforcement Learning](https://mlsanity.com/paper/2601.05466/) (2026)
- [Systematic Scaling Analysis of Jailbreak Attacks in Large Language Models](https://mlsanity.com/paper/2603.11149/) (2026)
- [Eyes-on-Me: Scalable RAG Poisoning through Transferable Attention-Steering Attractors](https://mlsanity.com/paper/2510.00586/) (2025)
- [VERA-V: Variational Inference Framework for Jailbreaking Vision-Language Models](https://mlsanity.com/paper/2510.17759/) (2025)
- [TrailBlazer: History-Guided Reinforcement Learning for Black-Box LLM Jailbreaking](https://mlsanity.com/paper/2602.06440/) (2026)
- [OptiLeak: Efficient Prompt Reconstruction via Reinforcement Learning in Multi-tenant LLM Services](https://mlsanity.com/paper/2602.20595/) (2026)
- [MemoPhishAgent: Memory-Augmented Multi-Modal LLM Agent for Phishing URL Detection](https://mlsanity.com/paper/2602.21394/) (2026)
- [MGC: A Compiler Framework Exploiting Compositional Blindness in Aligned LLMs for Malware Generation](https://mlsanity.com/paper/2507.02057/) (2025)
- [A Systematic Investigation of RL-Jailbreaking in LLMs](https://mlsanity.com/paper/2605.07032/) (2026)
- [Model-Agnostic Lifelong LLM Safety via Externalized Attack-Defense Co-Evolution](https://mlsanity.com/paper/2605.13411/) (2026)
- [Truth Lies Deep: Countering Semantic Camouflage via Latent Intent Verification](https://mlsanity.com/paper/2608.20378/) (2026)

## Abstract (arXiv)

Modern large language model (LLM) developers typically conduct a safety alignment to prevent an LLM from generating unethical or harmful content. Recent studies have discovered that the safety alignment of LLMs can be bypassed by jailbreaking prompts. These prompts are designed to create specific conversation scenarios with a harmful question embedded. Querying an LLM with such prompts can mislead the model into responding to the harmful question. The stochastic and random nature of existing genetic methods largely limits the effectiveness and efficiency of state-of-the-art (SOTA) jailbreaking attacks. In this paper, we propose RL-JACK, a novel black-box jailbreaking attack powered by deep reinforcement learning (DRL). We formulate the generation of jailbreaking prompts as a search problem and design a novel RL approach to solve it. Our method includes a series of customized designs to enhance the RL agent's learning efficiency in the jailbreaking context. Notably, we devise an LLM-facilitated action space that enables diverse action variations while constraining the overall search space. We propose a novel reward function that provides meaningful dense rewards for the agent toward achieving successful jailbreaking. Through extensive evaluations, we demonstrate that RL-JACK is overall much more effective than existing jailbreaking attacks against six SOTA LLMs, including large open-source models and commercial models. We also show the RL-JACK's resiliency against three SOTA defenses and its transferability across different models. Finally, we validate the insensitivity of RL-JACK to the variations in key hyper-parameters.