Senior IT Security Analyst

La Fosse; Greater London; On-site; GBP 90,000 - 130,000; Full time

Job summary

La Fosse is seeking a senior technical contributor within a global cyber security team to own selected domains end-to-end and drive improvements to reduce cyber risk.

The role spans analyst and engineering duties across security tools, vulnerability management, web and email security, incident response, and threat-informed remediation. Collaboration with infrastructure, cloud, application, identity and business teams is essential to deliver measurable improvements to the cyber defence posture.

Qualifications

• Senior technical contributor in cyber or infrastructure security.
• Owned or contributed to cyber security domains such as endpoint security, vulnerability management, identity security, network security, incident response or M365/Azure security.
• Experience with CrowdStrike Falcon for endpoint protection, EDR investigations and response workflows.
• Experience with Zscaler ZIA/ZPA for secure web access and troubleshooting.
• Leading or supporting vulnerability and exposure management programmes including risk prioritisation and remediation tracking.
• Strong knowledge of real-world attacker TTPs and MITRE ATT&CK to prioritise mitigations.
• Experience conducting security investigations and incident response activities.
• Ability to translate threat intelligence into actionable security improvements.
• Collaborating with cross-functional teams to deliver security improvements.
• Scripting/automation to improve security outcomes.

Responsibilities

• Own cyber security domains end-to-end and drive measurable improvements.
• Collaborate with infrastructure, cloud, application, identity and business teams.
• Analyse detections and support incident response.
• Translate threat intel into actionable mitigations.
• Lead or support vulnerability management programmes.
• Design and tune security tools and policies.
• Prioritise remediation based on risk and exposure.
• Deliver measurable improvements to cyber defence posture.

Skills

CrowdStrike Falcon

Zscaler ZIA/ZPA

Vulnerability management

Threat intelligence

MITRE ATT&CK

Incident response

Automation / scripting

EDR investigations

Threat hunting

Tools

CrowdStrike Falcon

Zscaler ZIA/ZPA

Vulnerability management tools

Threat intelligence platforms

Job description

This role is a senior technical contributor within a global cyber security team, owning selected cyber security domains end-to-end and driving practical improvements to reduce cyber risk.

The role combines analyst and engineering responsibilities across security tools, vulnerability and exposure management, web and email security, incident response, and threat-informed remediation.

The role works closely with infrastructure, cloud, application, identity and business teams to identify security issues, prioritise actions based on real-world attacker behaviour, and deliver measurable improvements to the cyber defence posture.

The successful candidate can demonstrate that they have:

• Operated as a senior technical contributor in cyber or infrastructure security.
• Owned or materially contributed to one or more cyber security domains, such as endpoint security, vulnerability management, identity security, network security, incident response or Microsoft 365 / Azure security.
• Used CrowdStrike or equivalent EDR tooling to investigate detections, support incident response and improve endpoint security controls.
• Used Zscaler ZIA/ZPA or equivalent secure web gateway, private access, zero trust or network access security technologies.
• Performed vulnerability assessment, exposure analysis or remediation prioritisation across enterprise technology environments.
• Applied threat intelligence, MITRE ATT&CK or exploitation-based evidence to prioritise mitigations.
• Supported or led cyber security investigations and incident response activities.
• Collaborated with infrastructure, cloud, application, identity and business teams to deliver security improvements.
• Used scripting, queries, automation or data analysis to improve security outcomes.

You will need:

• Strong hands-on experience administering, tuning and operationalising CrowdStrike Falcon, including endpoint protection, EDR investigations, detection analysis and response workflows.
• Strong hands-on experience administering and supporting Zscaler ZIA and ZPA, including policy design, access control, traffic analysis and security troubleshooting.
• Practical experience leading or supporting vulnerability and exposure management programmes, including vulnerability analysis, risk-based prioritisation, remediation tracking and validation of control effectiveness.
• Strong knowledge of real-world attacker tactics, techniques and procedures (TTPs) and the ability to translate threat intelligence, attack paths and exploitation trends into actionable security improvements.
• Experience conducting security investigations and incident response activities, including alert triage, root cause analysis, containment, remediation and lessons learned.