Technology Tales

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OWASP Top 10 for Large Language Model Applications

21st January 2024

OWASP stands for Open Web Application Security Project, and it is an online community dedicated to web application security. They are well known for their Top 10 Web Application Security Risks and late last year, they added a Top 10 for
Large Language Model (LLM) Applications.

Given that large language models made quite a splash last year, this was not before time. ChatGPT gained a lot of attention (OpenAI also has had DALL-E for generation of images for quite a while now), there are many others with Anthropic Claude and Perplexity also being mentioned more widely.

Figuring out what to do with any of these is not as easy as one might think. For someone more used to working with computer code, using natural language requests is quite a shift when you no longer have documentation that tells what can and what cannot be done. It is little wonder that prompt engineering has emerged as a way to deal with this.

Others have been plugging in LLM capability into chatbots and other applications, so security concerns have come to light, so far, I have not heard anything about a major security incident, but some are thinking already about how to deal with AI-suggested code that other already are using more and more.

Given all that, here is OWASP’s summary of their Top 10 for LLM Applications. This is a subject that is sure to draw more and more interest with the increasing presence of artificial intelligence in our everyday working and no-working lives.

LLM01: Prompt Injection

This manipulates an LLM through crafty inputs, causing unintended actions by the LLM. Direct injections overwrite system prompts, while indirect ones manipulate inputs from external sources.

LLM02: Insecure Output Handling

This vulnerability occurs when an LLM output is accepted without scrutiny, exposing backend systems. Misuse may lead to severe consequences such as Cross-Site Scripting (XSS), Cross-Site Request Forgery (CSRF), Server-Side Request Forgery (SSRF), privilege escalation, or remote code execution.

LLM03: Training Data Poisoning

This occurs when LLM training data is tampered, introducing vulnerabilities or biases that compromise security, effectiveness, or ethical behaviour. Sources include Common Crawl, WebText, OpenWebText and books.

LLM04: Model Denial of Service

Attackers cause resource-heavy operations on LLMs, leading to service degradation or high costs. The vulnerability is magnified due to the resource-intensive nature of LLMs and the unpredictability of user inputs.

LLM05: Supply Chain Vulnerabilities

LLM application lifecycle can be compromised by vulnerable components or services, leading to security attacks. Using third-party datasets, pre-trained models, and plugins can add vulnerabilities.

LLM06: Sensitive Information Disclosure

LLMs may inadvertently reveal confidential data in its responses, leading to unauthorized data access, privacy violations, and security breaches. It’s crucial to implement data sanitization and strict user policies to mitigate this.

LLM07: Insecure Plugin Design

LLM plugins can have insecure inputs and insufficient access control. This lack of application control makes them easier to exploit and can result in consequences such as remote code execution.

LLM08: Excessive Agency

LLM-based systems may undertake actions leading to unintended consequences. The issue arises from excessive functionality, permissions, or autonomy granted to the LLM-based systems.

LLM09: Overreliance

Systems or people overly depending on LLMs without oversight may face misinformation, miscommunication, legal issues, and security vulnerabilities due to incorrect or inappropriate content generated by LLMs.

LLM10: Model Theft

This involves unauthorized access, copying, or exfiltration of proprietary LLM models. The impact includes economic losses, compromised competitive advantage, and potential access to sensitive information.


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