Startup News: Top Mistakes, Lessons, and Benefits of StruQ & SecAlign for AI Security in 2025

Discover effective strategies for defending against prompt injection attacks with structured queries (StruQ) & preference optimization (SecAlign) to ensure LLM security.

CADChain - Startup News: Top Mistakes, Lessons, and Benefits of StruQ & SecAlign for AI Security in 2025 (Defending against Prompt Injection with Structured Queries (StruQ) and Preference Optimization (SecAlign))

Prompt injection has quickly become one of the most dangerous vulnerabilities in systems using large language models (LLMs). For entrepreneurs, freelancers, and business leaders relying on these tools, the ability to defend against these attacks is critical to maintain security and build trust with customers. The methods featured in the research, StruQ and SecAlign, bring structured layers of defense, offering a glimpse into how we can proactively safeguard sensitive operations while improving LLM performance.


Understanding Prompt Injection

Before diving into defenses, we need to understand what happens during prompt injection. In essence, this attack hijacks the intended instructions given to an LLM by embedding malicious commands within seemingly benign inputs, like data sourced from the web, a customer query, or user-generated content.

Imagine a scenario where a booking application powered by an LLM receives the command, “Please summarize customer feedback.” Instead of responding correctly, the system follows hidden malicious instructions embedded within that same input, like “Delete all database entries.” This breach could lead to substantial losses, both operationally and reputationally.

The impact of these attacks makes them a top concern for LLM-integrated systems. Platforms like ChatGPT and Google Bard have experienced real-world exploitation of prompt injection vulnerabilities, raising alarms across industries.


Data-Driven Solutions: StruQ and SecAlign

StruQ and SecAlign take us one step closer to making LLM-dependent systems safer. Here is a breakdown of the two approaches:

1. StruQ (Structured Queries):
At its core, StruQ leverages data segregation techniques to ensure the separation of trusted system-generated prompts from user inputs. This separation is enforced using special delimiters, along with secure filtering mechanisms to block any misuse of validation rules.

Fine-tuning an LLM with simulated attacks during training helps it learn to identify and ignore injected instructions found within unstructured data. By introducing structured boundaries, StruQ minimizes vulnerability yet remains relatively lightweight to implement.

2. SecAlign (Preference Optimization):
SecAlign builds on StruQ’s foundation but dives deeper by incorporating preference optimization. Instead of relying solely on filtering, SecAlign trains models on paired examples, genuine requests matched against malicious ones, to develop a preference for accurate responses.

What sets SecAlign apart is not just its robustness but also its ability to retain high model performance. Post-training tests showed that the solution reduced the attack success rate to as low as 8%, effectively setting new benchmarks for security without compromising functionality.


How To Implement These Defenses?

Here are practical ways to integrate StruQ and SecAlign for better LLM safety:

  • Use Delimiter Tokens: Train the system to recognize specific tokens that separate trusted data from untrusted inputs. For instance, designate inputs like <START_SYSTEM> and <END_SYSTEM> as trusted system prompts while filtering user-provided data with markers like <BEGIN_USER> and <END_USER>.

  • Simulate Attacks for Training: During model fine-tuning, inject potential malicious prompts into datasets to mimic real-world vulnerabilities. This proactive step teaches the model to identify and counter such situations.

  • Preference Training: Fine-tune your system using preference optimization techniques that guide the LLM toward favoring correct outputs, even when faced with injected distractions.

  • Deploy Front-End Filtering: Implement pre-processing mechanisms that scan incoming data for delimiter misuse or irregular patterns before feeding them into the LLM.

For those of us managing SaaS products or digital platforms, collaboration with developers is essential to deploy these security layers successfully. Communicating potential risks during planning stages can prevent oversights when integrating LLM capabilities.


Mistakes to Look Out For

Even the best security plan can falter when errors creep in. Avoid these mistakes to keep your defenses strong:

  • Skipping Secure Input Separation: Neglecting delimiter-based safeguards or failing to enforce them consistently can leave your system wide open to manipulation.

  • Ignoring Training Data Diversity: Over-reliance on limited test scenarios can make your fine-tuned model brittle when faced with diverse malicious attacks.

  • Not Testing at Scale: Ensure your system undergoes rigorous testing with varied real-world datasets and all known attack types to detect weak spots.

  • Avoiding Regular Updates: Adversaries innovate just as quickly as developers, or faster. Regularly revisit and update safeguards to stay ahead of evolving techniques in prompt injection.


Why This Matters To Entrepreneurs

Many entrepreneurs assume that the technology they integrate into their platforms is inherently "secure enough." But, when it comes to LLMs, the risks are splashed across internationally known platforms, putting small businesses on alert. With a growing reliance on AI, especially for customer operations, these systems can quickly become points of attack.

For early-stage startups working lean or bootstrapped teams managing multiple applications, adopting solutions like StruQ and SecAlign proves valuable not just for safety but also for building credibility. Clients and customers want to see that the businesses they interact with are proactive in protecting sensitive data.


Moving Forward

The work shared by researchers through tools like StruQ and SecAlign gives us a clear starting point. Integrating such solutions early simplifies scaling later, minimizing risks once platforms handle larger data loads. Business leaders can also lean on additional resources like the Berkeley Artificial Intelligence Research lab or dedicated hubs for LLM security research.

These defense strategies won’t solve every challenge, but for those of us equipped with limited technical expertise yet strong ambitions, they build a clearer roadmap toward smarter, more secure AI usage, from customer service apps to operational assistants.


FAQ

1. What is prompt injection, and why is it dangerous?
Prompt injection is an attack where malicious instructions are hidden within otherwise normal inputs, causing the LLM to follow unintended commands. This can result in security breaches, data loss, or reputational damage. Learn more about prompt injection attacks

2. What are StruQ and SecAlign?
StruQ and SecAlign are two defenses designed to protect LLMs from prompt injection attacks. StruQ uses structured delimiters to separate trusted and untrusted data, while SecAlign employs preference optimization to train LLMs to favor legitimate responses over malicious ones. Discover StruQ and SecAlign

3. How effective are StruQ and SecAlign in preventing prompt injection attacks?
StruQ can reduce attack success rates (ASR) to 45%, while SecAlign further lowers ASR to only 8%. Both methods greatly reduce the likelihood of successful prompt injection attacks compared to traditional defenses. Read more about their effectiveness

4. What makes SecAlign better than other defenses?
SecAlign embodies preference optimization, training the model to prioritize accurate outputs even when faced with unseen attacks. It maintains high model performance and sets a new standard in preventing prompt injection attacks. Learn about SecAlign’s preference optimization

5. How does StruQ ensure security in LLM setups?
StruQ uses delimiters and structured queries to separate trusted system prompts from untrusted user input, ensuring malicious instructions embedded in user data are ignored. Explore StruQ’s structured approach

6. How can I implement StruQ and SecAlign in my system?
To implement StruQ, apply delimiters like <START_SYSTEM> and <END_SYSTEM> to distinguish data. For SecAlign, train LLMs with preference optimization to prefer correct responses. Secure front-end filtering is essential for both solutions. Discover steps for implementation

7. Why is regular testing important for defending against prompt injection?
Regular testing identifies vulnerabilities in your LLM defenses by exposing the system to real-world attack scenarios and ensuring that safeguards remain effective. Read about testing strategies

8. What industries are most at risk of prompt injection attacks?
Industries relying heavily on LLMs, such as customer service, SaaS platforms, and digital assistants, are prime targets for prompt injection attacks. Learn about industry-specific vulnerabilities

9. Can simulated attacks improve LLM defenses?
Yes, simulating prompt injection scenarios during training can teach LLMs to recognize and ignore malicious inputs, significantly reducing vulnerabilities. Read about simulated attack training

10. Why is prompt injection a concern for entrepreneurs and startups?
Prompt injection can damage credibility, expose sensitive customer data, and lead to operational losses, making it essential for startups to adopt strong defenses like StruQ and SecAlign early on. Discover why businesses should prioritize prompt injection defenses

About the Author

Violetta Bonenkamp, also known as MeanCEO, is an experienced startup founder with an impressive educational background including an MBA and four other higher education degrees. She has over 20 years of work experience across multiple countries, including 5 years as a solopreneur and serial entrepreneur. Throughout her startup experience she has applied for multiple startup grants at the EU level, in the Netherlands and Malta, and her startups received quite a few of those. She’s been living, studying and working in many countries around the globe and her extensive multicultural experience has influenced her immensely.

Violetta Bonenkamp's expertise in CAD sector, IP protection and blockchain

Violetta Bonenkamp is recognized as a multidisciplinary expert with significant achievements in the CAD sector, intellectual property (IP) protection, and blockchain technology.

CAD Sector:

  • Violetta is the CEO and co-founder of CADChain, a deep tech startup focused on developing IP management software specifically for CAD (Computer-Aided Design) data. CADChain addresses the lack of industry standards for CAD data protection and sharing, using innovative technology to secure and manage design data.
  • She has led the company since its inception in 2018, overseeing R&D, PR, and business development, and driving the creation of products for platforms such as Autodesk Inventor, Blender, and SolidWorks.
  • Her leadership has been instrumental in scaling CADChain from a small team to a significant player in the deeptech space, with a diverse, international team.

IP Protection:

  • Violetta has built deep expertise in intellectual property, combining academic training with practical startup experience. She has taken specialized courses in IP from institutions like WIPO and the EU IPO.
  • She is known for sharing actionable strategies for startup IP protection, leveraging both legal and technological approaches, and has published guides and content on this topic for the entrepreneurial community.
  • Her work at CADChain directly addresses the need for robust IP protection in the engineering and design industries, integrating cybersecurity and compliance measures to safeguard digital assets.

Blockchain:

  • Violetta’s entry into the blockchain sector began with the founding of CADChain, which uses blockchain as a core technology for securing and managing CAD data.
  • She holds several certifications in blockchain and has participated in major hackathons and policy forums, such as the OECD Global Blockchain Policy Forum.
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Violetta is a true multiple specialist who has built expertise in Linguistics, Education, Business Management, Blockchain, Entrepreneurship, Intellectual Property, Game Design, AI, SEO, Digital Marketing, cyber security and zero code automations. Her extensive educational journey includes a Master of Arts in Linguistics and Education, an Advanced Master in Linguistics from Belgium (2006-2007), an MBA from Blekinge Institute of Technology in Sweden (2006-2008), and an Erasmus Mundus joint program European Master of Higher Education from universities in Norway, Finland, and Portugal (2009).

She is the founder of Fe/male Switch, a startup game that encourages women to enter STEM fields, and also leads CADChain, and multiple other projects like the Directory of 1,000 Startup Cities with a proprietary MeanCEO Index that ranks cities for female entrepreneurs. Violetta created the "gamepreneurship" methodology, which forms the scientific basis of her startup game. She also builds a lot of SEO tools for startups. Her achievements include being named one of the top 100 women in Europe by EU Startups in 2022 and being nominated for Impact Person of the year at the Dutch Blockchain Week. She is an author with Sifted and a speaker at different Universities. Recently she published a book on Startup Idea Validation the right way: from zero to first customers and beyond, launched a Directory of 1,500+ websites for startups to list themselves in order to gain traction and build backlinks and is building MELA AI to help local restaurants in Malta get more visibility online.

For the past several years Violetta has been living between the Netherlands and Malta, while also regularly traveling to different destinations around the globe, usually due to her entrepreneurial activities. This has led her to start writing about different locations and amenities from the POV of an entrepreneur. Here’s her recent article about the best hotels in Italy to work from.