Senior Security Analyst 24/7 (f/m/d) @ A1 Competence Delivery Center

Strength. Care. Growth

A1 Competence Delivery Center is a vital component of A1’s telecommunications business. Acting as an expertise hub, CDC is dedicated to delivering a full range of high-quality IT, network, financial and other services to support A1’s operations across all OpCos, independent of location.

Using the power of being OneGroup and leveraging synergies, CDC enables transparency of resources, key skills and knowledge expansion and personal career growth opportunities’ enhancement, paired with job stability.

You will know we are the right place for you, if you are driven by:

• Opportunities to learn and build your career.
• Meaningful work in a stable and fast-paced company.
• Diversity of people, projects, and platforms.
• A supportive, fun, and inspiring place to work.

Role Overview:

You will be responsible for continuously monitoring and analyzing the organization’s security posture. The role focuses on identifying, investigating, and helping to mitigate risks and vulnerabilities to ensure the protection of data, infrastructure, and systems.

Role insights:

• Leading in-depth investigations of escalated security incidents.
• Performing advanced threat analysis and forensic triage.
• Correlating data across multiple sources (SIEM, EDR, threat intel) to identify patterns and root causes.
• Collaborating with Tier 1 analysts to guide and mentor them through incident handling.
• Developing and refining playbooks and detection use cases.
• Supporting incident response efforts and coordinating with internal stakeholders.
• Contributing to threat hunting activities and proactive security assessments.
• Continuously improving SOC workflows, detection logic, and automation.

What makes you unique:

• Minimum 2 years of experience in a SOC or cybersecurity operations role.
• Strong hands-on experience with SIEM platforms (Splunk, Sentinel) and EDR tools (Microsoft Defender for Endpoint).
• Solid understanding of incident response, alert lifecycle, and threat detection methodologies.
• Familiarity with frameworks like MITRE ATT&CK, NIST, or CIS Controls.
• Experience with scripting or automation (PowerShell, Python) is a plus.
• Relevant certifications such as SC-200, CompTIA CySA+, Splunk Certified Power User, or similar.
• Excellent analytical and communication skills.
• Ability to work independently and take ownership of investigations.
• German language skills are a bonus.

Our gratitude for the job done will be eternal, but we’ll also offer you:

•  Valuable experience in one of the fastest-growing and most innovative industries.
•  Challenging assignments with strong opportunities for personal and professional growth in a multinational environment.
•  Hybrid working model supporting a healthy work-life balance.
•  Thousands of online and in-person Learning opportunities for you to grow.
•  Modern, open, and friendly work environment that fosters continuous learning and the development of both technical and soft skills.
•  Special employee tariffs and a wide range of attractive employee benefits.