Enhancing User Security Through Privilege Analysis
A new method uses language models to identify user privilege variables in code.
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Table of Contents
In many software applications, controlling user permissions is crucial for keeping data secure. Programs often perform certain tasks, like logging in users and deciding what data they can access. These tasks can be sensitive since if attackers manage to gain more rights than they should, they can cause serious problems for the organization.
One of the main goals for those with bad intentions is to get or raise their privileges to access important data. When it comes to defending these programs and the organizations behind them, it’s essential to close the gaps that allow such attacks to succeed. While it is easier to find memory issues like buffer overflows, finding logical issues that affect user privileges can be more difficult and harmful.
To tackle these challenges, many security analysts first look for what we call user privilege related (UPR) variables in the code. These are the variables that are used in operations tied to user privileges. Identifying them helps focus the search on where the code might be vulnerable to attacks. This task can take a lot of time, so there’s a need for tools that can help make this process faster and more efficient.
The Role of Language Models in Security Analysis
Recently, a new approach using large language models (LLMs) has emerged to assist with finding UPR variables. These models can process and analyze code, aiming to help analysts spot these important variables, which can be a significant part of keeping software secure.
Our method combines traditional code analysis with the power of LLMs to assess how much each variable relates to user privileges. The aim here is to produce a UPR score for each variable, showing how close it is to user permissions.
By focusing on smaller pieces of code and evaluating them individually, our approach sidesteps the drawbacks of trying to analyze large sections of code all at once. Instead of receiving a long chunk of code, the model looks at code statements, which allows it to give more accurate ratings for each variable’s UPR score.
The score ranges from 0 to 10, where 0 means a variable has nothing to do with user permissions, and higher numbers indicate a closer relationship. After generating these scores, analysts can then look at the variables that scored high to confirm if they indeed represent UPR variables.
The Importance of Identifying UPR Variables
In any given software application, especially those that run on servers, it is vital to restrict what users can do. For example, if one user has certain rights, they should not be able to access another user’s data without proper authorization. If attackers manage to get a hold of sensitive credentials, they can find ways to exploit those privileges.
Because of this, many organizations regularly review their code to find possible vulnerabilities that could be exploited. Vulnerabilities generally fall into two categories: memory corruptions and logical bugs. Memory corruption is often simpler to exploit since it directly affects how the program runs. Logical bugs, on the other hand, might not cause problems during normal execution, making them harder to spot and fix.
The problem is that while some tools can automatically find memory errors, fewer effective options exist to uncover logic flaws. Many of these issues arise from poor coding practices, like hardcoding sensitive information in the source code.
Current Challenges in Identifying UPR Variables
Finding UPR variables can be quite challenging for several reasons. First, there are many types of variables that might be tied to user privileges. Examples include passwords, secret keys, tokens, and more. Recognizing UPR variables isn’t just about spotting certain keywords; rather, it requires understanding the context in which those variables are used.
There are existing methods to find UPR variables, but they often rely on heuristic techniques, which can be limited in scalability and accuracy. These methods may use patterns in variable names or simple checks, but they often fail to catch all relevant variables, especially in large codebases.
Since the security of a program often depends on how these variables interact with other pieces of code, it is crucial to analyze their relationships carefully. This presents another challenge, as it requires a deeper understanding of the application logic.
A New Workflow to Identify UPR Variables
To improve the process, we have developed a new workflow that leverages LLMs to assist human analysts in identifying UPR variables more effectively. The main goal of this workflow is to accurately score variables based on their relevance to user privileges while reducing the amount of time analysts need to spend.
Here’s a rough outline of how the workflow operates:
Code Analysis: The workflow begins by analyzing the source code to construct a program dependence graph (PDG). This graph visually presents how different code statements relate to one another, helping to identify dependencies.
Variable Subgraphs: From the PDG, specific subgraphs for each variable are created. These subgraphs focus on the parts of the code that directly involve the variable.
Statement Collection: The workflow collects statements from these subgraphs, essentially gathering all the relevant code around each variable.
LLM Evaluation: Each statement is then submitted to a large language model, which rates its significance in terms of user privilege issues.
Score Calculation: Finally, the scores from the rated statements are aggregated to produce a single UPR score for each variable, which represents how related it is to user privileges.
Manual Review: After obtaining the scores, analysts can manually review those variables that score above a certain threshold, focusing their efforts on the most promising candidates.
Experimental Results and Implications
Our testing of this workflow has shown promising results. The false positive rate-meaning how many wrongly identified UPR variables there are-was only about 13.49%. This indicates that the system is quite accurate, providing significantly fewer incorrect results compared to traditional heuristic methods.
Furthermore, when looking at the total number of UPR variables our method has identified, it was found to be substantially higher than those found through other means. This efficiency not only demonstrates the effectiveness of using LLMs but also suggests that organizations could save considerable time and resources when assessing their security.
This capability is essential, especially for larger organizations with extensive codebases, where manually checking every variable is simply not feasible. By concentrating on the variables identified as potentially risky, analysts can perform their work more efficiently and more effectively.
Conclusion
In summary, the introduction of a hybrid workflow that integrates LLMs into the process of identifying user privilege related variables represents a significant advancement in software security analysis. By leveraging the capabilities of these models alongside traditional code analysis techniques, it is possible to produce a more thorough and practical understanding of UPR variables.
Organizations benefit greatly from being able to automate parts of the process, effectively reducing the manual burden on security analysts while improving accuracy. As software continues to evolve and the threats faced grow more complex, tools like this will play a crucial role in maintaining security and protecting sensitive information.
The future of software security analysis looks encouraging with such advancements, and ongoing research is necessary to refine these workflows further and adapt them to various coding environments and languages. Building on this foundation, we can hope to develop even more effective solutions to safeguard our data against unauthorized access and exploitation.
Title: A hybrid LLM workflow can help identify user privilege related variables in programs of any size
Abstract: Many programs involves operations and logic manipulating user privileges, which is essential for the security of an organization. Therefore, one common malicious goal of attackers is to obtain or escalate the privileges, causing privilege leakage. To protect the program and the organization against privilege leakage attacks, it is important to eliminate the vulnerabilities which can be exploited to achieve such attacks. Unfortunately, while memory vulnerabilities are less challenging to find, logic vulnerabilities are much more imminent, harmful and difficult to identify. Accordingly, many analysts choose to find user privilege related (UPR) variables first as start points to investigate the code where the UPR variables may be used to see if there exists any vulnerabilities, especially the logic ones. In this paper, we introduce a large language model (LLM) workflow that can assist analysts in identifying such UPR variables, which is considered to be a very time-consuming task. Specifically, our tool will audit all the variables in a program and output a UPR score, which is the degree of relationship (closeness) between the variable and user privileges, for each variable. The proposed approach avoids the drawbacks introduced by directly prompting a LLM to find UPR variables by focusing on leverage the LLM at statement level instead of supplying LLM with very long code snippets. Those variables with high UPR scores are essentially potential UPR variables, which should be manually investigated. Our experiments show that using a typical UPR score threshold (i.e., UPR score >0.8), the false positive rate (FPR) is only 13.49%, while UPR variable found is significantly more than that of the heuristic based method.
Authors: Haizhou Wang, Zhilong Wang, Peng Liu
Last Update: 2024-07-09 00:00:00
Language: English
Source URL: https://arxiv.org/abs/2403.15723
Source PDF: https://arxiv.org/pdf/2403.15723
Licence: https://creativecommons.org/licenses/by/4.0/
Changes: This summary was created with assistance from AI and may have inaccuracies. For accurate information, please refer to the original source documents linked here.
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