Senior Security & Systems Administrator

A U.S. holding company of a major global chemical manufacturer, overseeing multiple affiliated companies across the United States, is seeking a Senior Security & Systems Administrator to join its Information Technology team.

This is a hands-on role combining cybersecurity, systems administration, Microsoft 365 security, and IT governance across the U.S. group companies. The position works closely with subsidiary IT teams, corporate and regional technology teams, managed service providers, and business stakeholders to strengthen security, standardize technology controls, reduce risk, and support the technology needs of affiliated companies.

The successful candidate will have a strong foundation in systems administration and cybersecurity, particularly within Microsoft 365 environments, along with strong analytical and problem-solving skills.

• Monitor and administer security platforms, alerts, vulnerabilities, and security controls across supported environments.
• Investigate and triage security events and coordinate containment, escalation, documentation, and remediation with internal teams, vendors, and security providers.
• Maintain and support incident-response procedures and follow-up remediation activities.
• Review emerging security threats and translate identified risks into practical technical controls.
• Coordinate remediation of critical vulnerabilities, security findings, and configuration issues.
• Participate in incident response activities, including occasional after-hours support when required.

• Administer and enhance Microsoft Entra , including Conditional Access, multifactor authentication, external identities, guest access, and related identity controls.
• Support privileged access management, role reviews, separation of duties, and secure authentication practices.
• Assess identity and application risks, including enterprise applications, permissions, service principals, and third-party integrations.
• Support Zero Trust initiatives across identity, endpoints, applications, data, and infrastructure.

• Administer and support Microsoft Intune, Windows Autopilot, device compliance, security baselines, application deployment, updates, and endpoint configuration.
• Coordinate endpoint security, vulnerability remediation, patching, inventory, and lifecycle management.
• Support mobile device management and application protection for company-owned and approved personal devices.
• Help develop standardized onboarding, offboarding, provisioning, recovery, and secure endpoint configuration processes.

• Support Microsoft 365 security and administration, including Defender XDR, Defender for Office 365, Defender for Cloud Apps, Purview, Exchange Online, SharePoint, One Drive, and Teams.
• Support data protection initiatives including sensitivity labeling, encryption, Data Loss Prevention (DLP), audit, retention, and secure information sharing.
• Identify and help remediate overshared or exposed information.
• Support secure adoption and governance of approved AI and Microsoft Copilot technologies.
• Support Microsoft 365 services, Azure resources, enterprise applications, and system integrations.

• Support network and secure-access technologies, including firewalls, VPN, secure web access, segmentation, and related network security controls.
• Coordinate network and cloud security changes with internal teams and external service providers.
• Support email and domain security, including anti-phishing controls, mail-flow security, SPF, DKIM, DMARC, and secure email configurations.

• Participate in security assessments, control reviews, risk analysis, and security validation activities.
• Maintain security metrics, dashboards, risk registers, remediation tracking, project status, and supporting documentation.
• Prepare clear technical and management reporting on security risks, projects, vulnerabilities, and remediation activities.
• Support internal and external audits by gathering evidence, documenting controls and gaps, and coordinating corrective actions.
• Contribute to IT and security policies, standards, procedures, and technology roadmaps.

• Provide hands-on technical support and consulting to affiliated companies, including organizations with limited internal IT resources.
• Assist with endpoint hardware/software upgrades, troubleshooting, and other systems…