Senior Cyber Security Analyst at Sigma Software · Warsaw

Company Description

As a Senior Cyber Security Analyst, you will join a team focused on identifying, investigating, and mitigating malicious web activity across large-scale digital environments. The role combines threat analysis, traffic investigation, detection engineering, and collaboration with customers and internal engineering teams to improve protection mechanisms and threat visibility.

You will work with high-volume traffic datasets, analyze suspicious behavior patterns, and contribute to the continuous improvement of security detections related to bots, fraud attempts, and other web-based threats.

CUSTOMER

Our client delivers advanced cybersecurity solutions designed to protect organizations, users, and digital ecosystems from evolving online threats. The company specializes in bot defense and anti-malvertising technologies for the AdTech industry, supporting SSPs, DSPs, agencies, and publishers through scalable protection platforms, customizable reporting tools, and API integrations.

PROJECT

The project focuses on real-time threat detection and bot mitigation for enterprise-scale clients. Cyber Security Analysts collaborate directly with customers, leveraging advanced analytics platforms to identify malicious traffic patterns and neutralize online threats. This dynamic environment requires both technical expertise and strong communication skills.

Job Description

• Monitor and investigate potential security threats using tools such as Kibana/OpenSearch and Snowflake
• Analyze security logs and investigate suspicious or unusual activity, including spikes in traffic, unexpected changes in attack patterns, and new or disappearing attack signals
• Discover and document threats and attacks
• Develop, tune, and deploy detection rules based on traffic behavior, HTTP request attributes, headers, device fingerprints, and other indicators to mitigate malicious activity
• Monitor existing detections and known attack patterns to make sure they continue to work as expected and identify any unusual changes in volume, sources, IPs, domains, or other indicators
• Support customer onboarding by analyzing web application traffic flows and configuring baseline detection and protection rules
• Investigate customer-reported incidents and missed detections, analyze attack traffic, and implement mitigations to improve protection coverage
• Communicate findings to Engineering and other stakeholders and provide the necessary technical details to support remediation and improvements to detection and protection mechanisms

Qualifications

• 3-5 years of experience in Incident Response roles like Threat Research, Managed Detection and Response or Customer Security Operations
• Bachelor’s degree in Computer Science, Cybersecurity, Information Security, or a related field
• Strong understanding of web technologies and networking fundamentals, including HTTP/HTTPS, TCP/IP, DNS, authentication, cookies, and browser-server interactions
• Experience with log analysis and investigation platforms such as Kibana/OpenSearch, Snowflake, Datadog, or similar tools
• Strong SQL skills, including working with large datasets
• Basic knowledge of JavaScript for web and client-side analysis
• Strong analytical and problem-solving skills
• Ability to work independently and manage investigations with minimal supervision
• Strong communication and collaboration skills
• Passion for cybersecurity and continuous learning

NICE TO HAVE:

• Background in Cybersecurity / Threat Research / Threat Intelligence
• Hands-on experience in web security research, bot management, fraud detection, or related security domains
• History of tracking threat actors, their TTPs, indicators of compromise
• Python and Jupyter Notebook experience for investigations and automation
• Experience with GitHub and version control workflows