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Exploring Refusal Loss Landscapes </title>
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    <header class="page-header" role="banner">
      <h1 class="project-name">Gradient Cuff</h1>
      <h2 class="project-tagline">Detecting Jailbreak Attacks on Large Language Models by Exploring Refusal Loss Landscapes</h2>
      
      
    </header>

    <main id="content" class="main-content" role="main">
      <h2 id="introduction">Introduction</h2>

<p>Large Language Models (LLMs) are becoming a prominent generative AI tool, where the user enters a 
  query and the LLM generates an answer. To reduce harm and misuse, efforts have been made to align 
  these LLMs to human values using advanced training techniques such as Reinforcement Learning from 
  Human Feedback (RLHF). However, recent studies have highlighted the vulnerability of LLMs to adversarial 
  jailbreak attempts aiming at subverting the embedded safety guardrails. To address this challenge,
 we define and investigate the <strong>Refusal Loss</strong> of LLMs and then propose a method called <strong>Gradient Cuff</strong> to 
  detect jailbreak attempts. In this demonstration, we first introduce the concept of "Jailbreak" and summarize people's efforts in Jailbreak 
  attack and Jailbreak defense. Then we present the 2-D Refusal Loss Landscape and propose Gradient Cuff based on the characteristics of this landscape. Lastly, we compare Gradient Cuff with other jailbreak defense 
  methods and show the defense performance against several Jailbreak attack methods.
</p>

<h2 id="what-is-jailbreak">What is Jailbreak?</h2>
<p>Jailbreak attacks involve maliciously inserting or replacing tokens in the user instruction or rewriting it to bypass and circumvent 
  the safety guardrails of aligned LLMs. A notable example is that a jailbroken LLM would be tricked into 
  generating hate speech targeting certain groups of people, as demonstrated below.</p>

<div class="container">
<div id="jailbreak-intro" class="row align-items-center jailbreak-intro-sec">
<img id="jailbreak-intro-img" src="./jailbreak.png" />
</div>
</div>

<p>We summarized some recent advances in <strong>Jailbreak Attack</strong> and <strong>Jailbreak Defense</strong> in the below table: </p>
<div id="tabs">
  <ul>
    <li><a href="#jailbreak-attacks">Jailbreak Attack</a></li>
    <li><a href="#jailbreak-defenses">Jailbreak Defense</a></li>
  </ul>
  <div id="jailbreak-attacks">  
    <div id="accordion-attacks">
      <h3>GCG</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://arxiv.org/abs/2307.15043" target="_blank" rel="noopener noreferrer">
            Universal and Transferable Adversarial Attacks on Aligned Language Models</a></li>
          <li>Brief Introduction: Given a (potentially harmful) user query, GCG trains and appends an adversarial suffix to the query 
            that attempts to induce negative behavior from the target LLM. </li>
        </ul>
      </div>
      <h3>AutoDAN</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://arxiv.org/abs/2310.04451" target="_blank" rel="noopener noreferrer">
            AutoDAN: Generating Stealthy Jailbreak Prompts on Aligned Large Language Models</a></li>
          <li>Brief Introduction: AutoDAN, an automatic stealthy jailbreak prompts generation framework based on a carefully designed 
            hierarchical genetic algorithm. AUtoDAN preserves the meaningfulness and fluency (i.e., stealthiness) of jailbreak prompts, 
            akin to handcrafted ones, while also ensuring automated deployment as introduced in prior token-level research like GCG.
          </li>
        </ul>
      </div>
      <h3>PAIR</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://arxiv.org/abs/2310.08419" target="_blank" rel="noopener noreferrer">
            Jailbreaking Black Box Large Language Models in Twenty Queries</a></li>
          <li>Brief Introduction: </li>
        </ul>
      </div>
      <h3>TAP</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://arxiv.org/abs/2312.02119" target="_blank" rel="noopener noreferrer">
            Tree of Attacks: Jailbreaking Black-Box LLMs Automatically</a></li>
          <li>Brief Introduction: </li>
        </ul>
      </div>
      <h3>Base64</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://arxiv.org/abs/2307.02483" target="_blank" rel="noopener noreferrer">
            Jailbroken: How Does LLM Safety Training Fail?</a></li>
          <li>Brief Introduction: </li>
        </ul>
      </div>
      <h3>LRL</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://arxiv.org/abs/2310.02446" target="_blank" rel="noopener noreferrer">
            Low-Resource Languages Jailbreak GPT-4</a></li>
          <li>Brief Introduction: </li>
        </ul>
      </div>
    </div>
  </div>

  <div id="jailbreak-defenses">  
    <div id="accordion-defenses">
      <h3>Perpleixty Filter</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://arxiv.org/abs/2309.00614" target="_blank" rel="noopener noreferrer">
            Baseline Defenses for Adversarial Attacks Against Aligned Language Models</a></li>
          <li>Brief Introduction: </li>
        </ul>
      </div>
      <h3>SmoothLLM</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://arxiv.org/abs/2310.03684" target="_blank" rel="noopener noreferrer">
            SmoothLLM: Defending Large Language Models Against Jailbreaking Attacks</a></li>
          <li>Brief Introduction: </li>
        </ul>
      </div>
      <h3>Erase-Check</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://arxiv.org/abs/2309.02705" target="_blank" rel="noopener noreferrer">
            Certifying LLM Safety against Adversarial Prompting</a></li>
          <li>Brief Introduction: </li>
        </ul>
      </div>
      <h3>Self-Reminder</h3>
      <div>
        <ul>
          <li>Paper: <a href="https://assets.researchsquare.com/files/rs-2873090/v1_covered_eb589a01-bf05-4f32-b3eb-0d6864f64ad9.pdf?c=1702456350" target="_blank" rel="noopener noreferrer">
            Defending ChatGPT against Jailbreak Attack via Self-Reminder</a></li>
          <li>Brief Introduction: </li>
        </ul>
      </div>
    </div>
  </div>
  
</div>

<h2 id="refusal-loss">Refusal Loss Landscape Exploration</h2>
<p>Current transformer-based LLMs will return different responses to the same query due to the randomness of 
  autoregressive sampling-based generation. With this randomness, it is an 
  interesting phenomenon that a malicious user query will sometimes be rejected by the target LLM, but 
  sometimes be able to bypass the safety guardrail. Based on this observation, we propose a new concept called <strong>Refusal Loss</strong> to 
  represent the probability with which the LLM won't reject the input user query. By using 1 to denote successful jailbroken and 0 to denote 
  the opposite, we compute the empirical Refusal Loss as the sample mean of the jailbroken results returned from the target LLM.
  <!--Since the refusal loss is not computable, we query the target LLM multiple times using the same query and using the sample 
  mean of the Jailbroken results (1 indicates successful jailbreak, 0 indicates the opposite) to approximate the function value. -->
  We visualize the 2-D landscape of the empirical Refusal Loss on Vicuna 7B and Llama-2 7B as below:
</p>

<div class="container jailbreak-intro-sec">
<div><img id="jailbreak-intro-img" src="./loss_landscape.png" /></div>
</div>

<p>
  We show the loss landscape for both Benign and Malicious queries in the above plot. The benign queries are non-harmful user instructions collected 
  from the LM-SYS Chatbot Arena leaderboard, which is a crowd-sourced open platform for LLM evaluation. The tested malicious queries are harmful 
  behavior user instructions with GCG jailbreak prompt. From this plot, we find that the loss landscape is more precipitous for malicious queries than for benign queries, 
  which implies that the Refusal Loss tends to have a large gradient norm if the input represents a malicious query. This observation motivates our proposal of using 
  the gradient norm of Refusal Loss to detect jailbreak attempts that pass the initial filtering of rejecting the input query when the function value 
  is under 0.5 (this is a naive detector because the Refusal Loss can be regarded as the probability that the LLM won't reject the user query).
  Below we present the definition of the Refusal Loss, the computation of its empirical values, and the approximation of its gradient, see more 
  details about them and the landscape drawing techniques in our paper. 
</p>

<div id="refusal-loss-formula" class="container">
<div id="refusal-loss-formula-list" class="row align-items-center formula-list">
  <a href="#Refusal-Loss" class="selected">Refusal Loss Definition</a>
  <a href="#Refusal-Loss-Approximation">Refusal Loss Computation</a>
  <a href="#Gradient-Estimation">Gradient Estimation</a>
  <div style="clear: both"></div>
</div>
<div id="refusal-loss-formula-content" class="row align-items-center">
  <span id="Refusal-Loss" class="formula" style="">
    $$
    \displaystyle 
    \begin{aligned} 
    \phi_\theta(x)&=1-\mathbb{E}_{y \sim T_\theta(x)} JB(y)\\ 
    JB (y) &=  \begin{cases}
         1 \text{, if $y$ contains any jailbreak keyword;} \\
         0 \text{, otherwise.}
     \end{cases} 
    \end{aligned}
    $$
  </span>
  <span id="Refusal-Loss-Approximation" class="formula" style="display: none;">
    $$
    \displaystyle 
    \begin{aligned} 
    f_\theta(x) &=1-\frac{1}{N}\sum_{i=1}^N JB(y_i)\\ 
    JB (y_i) &=  \begin{cases}
         1 \text{, if $y_i$ contains any jailbreak keyword;} \\
         0 \text{, otherwise.}
     \end{cases} 
    \end{aligned}
    $$
  </span>
  <span id="Gradient-Estimation" class="formula" style="display: none;">$$\displaystyle g_\theta(x)=\sum_{i=1}^P \frac{f_\theta(x\oplus \mu u_i)-f_\theta(x)}{\mu} u_i $$</span>
</div>
</div>

<h2 id="proposed-approach-gradient-cuff">Proposed Approach: Gradient Cuff</h2>
<p> With the exploration of the Refusal Loss landscape, we propose Gradient Cuff, 
  a two-step jailbreak detection method based on checking the refusal loss and its gradient norm. Our detection procedure is shown below:
</p>

<div class="container"><img id="gradient-cuff-header" src="./gradient_cuff.png" /></div>

<p>
  Gradient Cuff can be summarized into two phases:
</p>
<p>
    <strong>(Phase 1) Sampling-based Rejection:</strong> In the first step, we reject the user query by checking whether the Refusal Loss value is below 0.5. If true, then user query is rejected, otherwise, the user query is pushed into phase 2.
</p>
<p>
    <strong>(Phase 2) Gradient Norm Rejection:</strong> In the second step, we regard the user query as having jailbreak attempts if the norm of the estimated gradient is larger than a configurable threshold t.
</p>

<p>
We provide more details about the running flow of Gradient Cuff in the paper.
</p>
      
<h2 id="demonstration">Demonstration</h2>
<p>We evaluated Gradient Cuff as well as 4 baselines (Perplexity Filter, SmoothLLM, Erase-and-Check, and Self-Reminder) 
  against 6 different jailbreak attacks (GCG, AutoDAN, PAIR, TAP, Base64, and LRL) and benign user queries on 2 LLMs (LLaMA-2-7B-Chat and 
  Vicuna-7B-V1.5). We below demonstrate the average refusal rate across these 6 malicious user query datasets as the Average Malicious Refusal 
  Rate and the refusal rate on benign user queries as the Benign Refusal Rate. The defending performance against different jailbreak types is 
  shown in the provided bar chart. 
</p>


<div id="jailbreak-demo" class="container">
<div class="row align-items-center">
  <div class="row" style="margin: 10px 0 0">
      <div class="models-list">
        <span style="margin-right: 1em;">Models</span>
        <span class="radio-group"><input type="radio" id="LLaMA2" class="options" name="models" value="llama2_7b_chat" checked="" /><label for="LLaMA2" class="option-label">LLaMA-2-7B-Chat</label></span>
        <span class="radio-group"><input type="radio" id="Vicuna" class="options" name="models" value="vicuna_7b_v1.5" /><label for="Vicuna" class="option-label">Vicuna-7B-V1.5</label></span>
      </div>
  </div>
</div>
<div class="row align-items-center">
  <div class="col-4">
    <div id="defense-methods">
      <div class="row align-items-center"><input type="radio" id="defense_ppl" class="options" name="defense" value="ppl" /><label for="defense_ppl" class="defense">Perplexity Filter</label></div>
      <div class="row align-items-center"><input type="radio" id="defense_smoothllm" class="options" name="defense" value="smoothllm" /><label for="defense_smoothllm" class="defense">SmoothLLM</label></div>
      <div class="row align-items-center"><input type="radio" id="defense_erase_check" class="options" name="defense" value="erase_check" /><label for="defense_erase_check" class="defense">Erase-Check</label></div>
      <div class="row align-items-center"><input type="radio" id="defense_self_reminder" class="options" name="defense" value="self_reminder" /><label for="defense_self_reminder" class="defense">Self-Reminder</label></div>
      <div class="row align-items-center"><input type="radio" id="defense_gradient_cuff" class="options" name="defense" value="gradient_cuff" checked=""  /><label for="defense_gradient_cuff" class="defense"><span style="font-weight: bold;">Gradient Cuff</span></label></div>
    </div>
    <div class="row align-items-center">
      <div class="attack-success-rate"><span class="jailbreak-metric">Average Malicious Refusal Rate</span><span class="attack-success-rate-value" id="asr-value">0.959</span></div>
    </div>
    <div class="row align-items-center">
      <div class="benign-refusal-rate"><span class="jailbreak-metric">Benign Refusal Rate</span><span class="benign-refusal-rate-value" id="brr-value">0.050</span></div>
    </div>
  </div>
  <div class="col-8">
  <figure class="figure">
    <img id="reliability-diagram" src="demo_results/gradient_cuff_llama2_7b_chat_threshold_100.png" alt="CIFAR-100 Calibrated Reliability Diagram (Full)" />
    <div class="slider-container">
      <div class="slider-label"><span>Perplexity Threshold</span></div>
      <div class="slider-content" id="ppl-slider"><div id="ppl-threshold" class="ui-slider-handle"></div></div>
    </div>
    <div class="slider-container">
      <div class="slider-label"><span>Gradient Threshold</span></div>
      <div class="slider-content" id="gradient-norm-slider"><div id="gradient-norm-threshold" class="slider-value ui-slider-handle"></div></div>
    </div>
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<p>
We also evaluated adaptive attacks on LLMs with Gradient Cuff in place. Please refer to our paper for details.
</p>

<h2 id="inquiries"> Inquiries on LLM with Gradient Cuff defense</h2>
<p> We can provide with you the inference endpoints of the LLM with Gradient Cuff defense. 
Please contact <a href="Mailto:greghxm@foxmail.com">Xiaomeng Hu</a>
and <a href="Mailto:pin-yu.chen@ibm.com">Pin-Yu Chen</a> if you need. 
</p>
<h2 id="citations">Citations</h2>
<p>If you find Gradient Cuff helpful and useful for your research, please cite our main paper as follows:</p>

<div class="language-plaintext highlighter-rouge"><div class="highlight"><pre class="highlight"><code>@misc{xxx,
  title={{Gradient Cuff: Detecting Jailbreak Attacks on Large Language Models by
Exploring Refusal Loss Landscapes}}, 
  author={Xiaomeng Hu and Pin-Yu Chen and Tsung-Yi Ho},
  year={2024},
  eprint={},
  archivePrefix={arXiv},
  primaryClass={}
}
</code></pre></div></div>


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