SIEM Content Development Specialist

Vodafone Limited; Newbury; On-site; GBP 70,000 - 100,000; Full time

Benefits offered by this job

Yearly bonus

Annual leave 28 days

Private pension

Private medical

Share save scheme

Employee discounts

Job summary

Vodafone Limited is seeking a skilled SIEM Content Development Specialist to advance threat detection and response capabilities. You will design, test, and optimise SIEM content across multiple technologies, guiding analysts with effective detection logic and playbooks.

The role requires deep knowledge of SIEM/EDR systems, cloud and on-prem tools, and strong collaboration with CSOC and DevOps teams. A background in threat modelling and incident response is essential.

Qualifications

• 2–5 years’ experience in SIEM content development (rule logic and code)
• 2+ years of SOC analyst experience (Level2+)
• Hands-on security event analysis experience
• Deep knowledge of IPv4/IPv6 and TCP protocols
• Experience with SIEM/EDR rules and cloud/ on‑prem tools
• Proficient in version control (Git) and regex development

Responsibilities

• Design and develop detection content to identify malicious activity
• Tune threat and vulnerability management technologies for better detection accuracy
• Lead optimisation of SIEM content and adoption of cloud-native tools
• Manage lifecycle of detection content: develop, test, release, retire
• Collaborate with DevOps/SecOps to integrate content into CI/CD workflows
• Support security event analysis and threat response activities
• Contribute to security reports and post-incident lessons learned

Skills

SIEM content development

Threat detection

Blue team input

Networking (IPv4/IPv6)

Windows/Linux knowledge

Education

Bachelor's in CS/SEC

Tools

ArcSight

Sentinel

QRadar

Splunk

EDR tools

Job description

The SIEM Content Development Specialist plays a critical role in advancing the Cyber Security Operations Center's ability to detect and respond to cybersecurity incidents. This role focuses on designing and developing cutting-edge detection content leveraging a wide array of security technologies and telemetry to identify malicious activity and guide security analysts through effective response playbooks. Working within a threat-led framework, the specialist collaborates across teams to translate threat intelligence into actionable detection logic and response workflows. The position demands strong technical acumen, analytical thinking, and problem-solving capabilities, along with the ability to communicate clearly with peers, leadership, and cross-functional stakeholders. Key accountabilities and decision ownership:

• Contribute to continuous improvement initiatives across multiple technologies by developing and refining content that enhanced threat detection and response capabilities.
• Contribute to the development and optimisation of threat detection content, including the tuning of threat and vulnerability management technologies and the continual refinement of SIEM rules and logic to enhance detection accuracy and operational performance.
• Lead and contribute to the optimisation and modernisation of SIEM content, supporting the adoption of next-generation SIEM technologies and cloud-native security tools.
• Manage the lifecycle of detection content, including development, testing, release, and retirement, using version control and documentation best practices.
• Collaborate with DevOps/SecOps teams to integrate security content into broader CI/CD workflows
• Collaborate with the CSOC Manager to support improvements in security operations through effective content contributions.
• Support security event analysis by participating in and may drive security event analysis activities to address current cyber threats.
• Assist in threat response activities, providing analytical input from a blue team perspective to help identify potential threat group behaviours.
• Contribute to the creation of cyber security reports and advisories, ensuring timely and accurate dissemination to key stakeholders.
• Participate in residual risk assessments, supporting post-incident analysis and the documentation of operational and technical lessons learned.
• Collaborating with data owners and customers on understanding data sources and use cases and successfully translating requirements to actionable content.
• Minimum of 2-5 years' experience in SIEM content (rule logic and code) development role
• Minimum of 2 years of SOC analyst experience (Level2 or above) required.
• In depth and extensive hands-on experience in security event analysis, create and refine SIEM/EDR rules and deliver efficiency within the SIEM and all other technologies used within the team.
• Deep knowledge of IPv4/IPv6, TCP networking protocols
• Deep knowledge of Windows/Linux operating systems
• Exceptional working knowledge of security technologies such as SIEM (ArcSight, Sentinel, QRadar, LogRhythm, Splunk), EDR (Microsoft Defender, FireEye, Tanium), IDS/IPS, firewalls, proxies, web application firewalls, anti-virus, etc.
• Comprehensive understanding of Window Security Event logs and Syslog
• Excellent familiarity with endpoint/perimeter security attack vectors and detection (blue/purple teaming)
• Excellent familiarity with standard security frameworks such as MITRE, cyber kill chain and APT campaign strategies
• Outstanding knowledge of cloud platforms such as Azure, O365, Google cloud, AWS, Oracle
• Experience with modern SIEM platforms, including cloud-native or hybrid solutions
• Hands-on experience with CI/CD pipelines and automation tools for security content deployment.
• Proficiency in version control systems (e.g., Git) for managing SIEM content.
• Excellent working knowledge of regular expression development
• Scripting and programming experience is highly desirable
• Kusto or SQL knowledge, including rule/query optimisation
• Proven ability to prioritise workload, meet deadlines and utilise time effectively
• Good interpersonal and communication skills, works effectively as a team leader and the ability.
• Experience in security event analytics, for example Elastic, Azure Sentinel or Splunk.
• Deep understanding of threat actor techniques and tools

Preferred

• Demonstrable experience in critical thinking and data or logical analysis.
• Knowledge of: typical security devices such as firewalls, Intrusion detection system, anti-virus, anti-spam,
• Cyber threat concepts e.g. cyber kill chain, attack methods, threat actors.
• Cloud systems and Windows and Linux OS.
• Experience with investigating intrusions in Linux and cloud environments

Must have technical and professional qualifications

• 3 years or above related experience
• Excellent verbal and written communication skills
• Highly disciplined and motivated, able to work independently or under direction
• Deep understanding of threat actor techniques and tools

At Vodafone, we're not just shaping the future of connectivity for our customers - we're shaping the future for everyone who joins our team. When you work with us, you're part of a global mission to connect people, solve complex challenges, and create a sustainable and more inclusive world. If you want to grow your career whilst finding the perfect balance between work and life, Vodafone offers the opportunities to help you belong and make a real impact., We are a leading international Telco, serving millions of customers. At Vodafone, we believe that connectivity is a force for good. If we use it for the things that really matter, it can improve people's lives and the world around us. Through our technology we empower people, connecting everyone regardless of who they are or where they live and we protect the planet, whilst helping our customers do the same.

Belonging at Vodafone isn't a concept; it's lived, breathed, and cultivated through everything we do. You'll be part of a global and diverse community, with many different minds, abilities, backgrounds and cultures. ;We're committed to increase diversity, ensure equal representation, and make Vodafone a place everyone feels safe, valued and included. If you require any reasonable adjustments or have an accessibility request as part of your recruitment journey, for example, extended time or breaks in between online assessments, please refer to for guidance. Together we can. Vodafone is committed to attracting, developing and retaining the very best people by offering a motivating and inclusive workplace in which talent is truly recognised and rewarded. We are committed to promoting Inclusion for All with the belief that diversity plays an important role in the success of our business. We actively encourage everyone to consider becoming a part of our journey.

• Yearly bonus: 10%
• Annual leave: 28 days + bank holidays + the opportunity to buy/sell/carry over 5 days/year
• Charity days: 5 days/year
• Maternity leave: 52 weeks: the first 13 weeks are fully paid, followed by 26 weeks of half pay
• Private pension: You can contribute up to 5% of your basic pay with 2:1 matching from Vodafone up to 10%.
• Access to: private medical, private dental, free health assessments, share save scheme
• Additional discounts: Vodafone retail, gym, cinema, cycle to work, season ticket loan