Working Student Research Engineer – WAF Signatures

BE ONE STEP AHEAD: Help us make the internet a safer place
The digital world is a relentless storm of evolving cyber threats. IT professionals are on the front lines, defending their organizations' most valuable assets against increasingly sophisticated attacks.

As one of the leading providers of cyber security solutions, at Link11, we understand the pressure and want to protect companies and organizations through meticulous attention to detail and early integration of cutting-edge methods. We take full responsibility for our clients' security, and we are constantly exploring new and improved ways to enhance their protection. Our reputation is built on providing enterprise-grade cybersecurity solutions that secure IT networks and critical applications, allowing companies to focus on their core business operations.

We have extended our proven expertise in Network Security, Web Protection and Web Performance and leveraged the know-how of Reblaze Technologies to enhance our portfolio, particularly in the realm of WAAP (Web Application and API Protection). Our comprehensive security platform reflects our dedicated commitment to client security and proactive defense strategies – making the Internet a safer place.

We at Link11 are a team of passionate people, driven by a common mission to make the Internet safer. More than 100 employees work across our international locations – Frankfurt, Tel Aviv and Vancouver – some 100% remotely. Are you highly motivated and looking for a challenging and rewarding career where you can make a real difference? Then you are very welcome at Link11. Shape our digital future with Link11.

Your future challenges:

• Analyze the current OWASP Core Rule Set architecture, rule logic, and detection mechanisms to understand coverage, performance characteristics, and limitations.
• Research and document the technical requirements for developing custom signature rules that maintain or improve upon CRS detection capabilities.
• Design a proof-of-concept framework for converting selected CRS rules into Link11's signature format, testing effectiveness against common attack vectors
• Document migration pathways, potential risks, and recommendations for implementation strategy
• Collaborate with our WAAP engineering teams to validate findings and align research with production requirements

Your Skills:

• You are studying for a Bachelor's or Master's degree
• Strong understanding of web application security fundamentals (OWASP Top 10, common attack vectors like SQL injection, XSS, RCE)
• Knowledge of regular expressions (regex) and pattern matching techniques
• Familiarity with HTTP/HTTPS protocols, request/response structures, and web traffic analysis
• Proficiency in at least one scripting language (Python, Bash, Perl) for automation and analysis
• Analytical mindset with good research and documentation skills
• You are capable of working both independently and as part of a team.
• You have excellent communication skills, at least in English or German.

We are Link11:

• We live our startup mentality at heart. The professional framework gives us the growth and stability of Link11- founded in 2005. We are still strong today working alongside the founders and the management team.
• We are full of energy, have short decision-making paths and bring changes directly on the way.
• We live a positive, interactive and appreciative working atmosphere in which all employees can contribute.
• We encourage the further development of our employees.
• We are willing to leave our comfort zone for innovation and improvement because we want to be the best in the market.
• We have received several awards for our forward-looking solutions

Link11 is the right place for you:

• Become part of a highly motivated team in which we treat each other with respect.
• Meet your colleagues at eye level. We are all equal and without barriers.
• Live and develop your strengths in a friendly atmosphere.
• Organise yourself in a flexible working model, because you are more than just your job.
• Lead us to success with your skills.
• Community is the trump card: team events, sundowners, after work parties bring us together (also internationally).
• Taking care of our team doesn't end at the coffee machine or a filled fruit basket
• Look forward to interesting benefits such as fitness, JobRad, support for daycare fees and much more. We are cooperation partners of national and international associations and authorities.

Information and contact
Do you have any questions about this position? Contact us directly at Your contact person is Nadine Saewert from the People Management department.

We look forward to getting to know you and learning more about you as a person and your professional career.

Got it? Then simply apply via our careers page at , stating your salary expectations and your soonest possible starting date.

We promise we will reply to you within 48 hours of receiving your application with feedback on whether we can get together for a telephone interview

Link11 GmbH
Lindleystrasse 12

D-60314 Frankfurt am Main