Senior Security Administrator

Alpha & Omega Semiconductor; Sunnyvale (CA); On-site; USD 120,000 - 170,000; Full time

Job summary

Alpha & Omega Semiconductor is seeking a hands-on Senior Security Administrator to strengthen our cybersecurity program. The role supports security controls across endpoints, networks, identity, email security, and vulnerability management, aligning with NIST CSF.

This is a temporary position with potential to transition to full-time. You will collaborate with IT Infrastructure, automation teams and external vendors to reduce cyber risk and prepare audit evidence and security documentation for

Qualifications

• 5+ years in IT security, security administration or cybersecurity operations.
• Hands-on with endpoint security, firewalls, vulnerability management, SIEM, MFA, AD and VPN.
• Ability to investigate alerts, review logs, and coordinate remediation with teams.
• Familiarity with NIST CSF, CIS Controls, ISO 27001 or similar frameworks.
• Experience supporting audits, access reviews and evidence collection.

Responsibilities

• Monitor and triage security alerts from SIEM, EDR, firewall, and DLP tools.
• Administer and support Cisco FirePower, McAfee and other security technologies.
• Operate vulnerability management, remediation tracking, and reporting.
• Support identity and access management activities including MFA and VPN control.
• Assist phishing investigations, malware response, and incident containment.
• Participate in incident response, documentation and lessons learned.
• Prepare audit evidence, control docs, diagrams and review records.
• Coordinate with internal teams and vendors to boost security operations and readiness.

Skills

Endpoint security

Firewalls

Vulnerability management

SIEM/log monitoring

MFA

Active Directory

Microsoft Entra ID

VPN

Email security

NIST CSF

Tools

Cisco FirePower

McAfee Endpoint/DLP

SecureWorks Redcloak

Imap/ITAP SIEM

OpenDNS/Cisco Umbrella

Imperva WAF

ManageEngine PAM

Nessus

Proofpoint

Job description

At Alpha and Omega Semiconductor (AOS), we design, develop and globally supply a broad range of power semiconductors, including a wide portfolio of Power MOSFET, IGBT, IPM, TVS, GaN/SiC, Power IC and Digital Power products. You will find our products in everyday applications including personal computers, graphic cards, gaming consoles, TVs, home appliances, smart phones, power tools, and more! At the center of our innovation is our people who bring passion, talent, and a collaborative atmosphere to our growing company. We offer an impressive benefit package and career development opportunities. If you are ready to take the next step in your career working with a team of passionate and talented people, then take a look at the job opportunity below to POWER your career!

Overview

AOS is seeking a hands‑on Senior Security Administrator to support and strengthen the company's cybersecurity program. This role will help operate, monitor, and improve security controls across endpoints, networks, identity and access, email security, vulnerability management, logging, incident response, and audit readiness. The position works closely with IT Infrastructure, Automation, business application teams, and external security vendors to reduce cyber risk and support continuous improvement aligned with the NIST Cybersecurity Framework. This is a temporary position with the opportunity to transition to a regular full‑time role.

Primary Job Responsibilities

• Monitor and triage security alerts from SIEM/log management, endpoint protection, EDR, firewall, DNS security, WAF, DLP, vulnerability scanning, and security rating tools.
• Administer and support AOS security technologies, including Cisco FirePower, McAfee Endpoint/DLP, SecureWorks Redcloak, IMAP/ITAP SIEM, OpenDNS/Cisco Umbrella, Imperva WAF/DDoS, ManageEngine PAM, Nessus, Microsoft Entra ID/MFA, and Proofpoint or equivalent email security tools.
• Operate vulnerability management processes, including scanning, risk prioritization, remediation tracking, exception documentation, and reporting.
• Support identity and access management activities, including MFA enforcement, VPN access control, privileged access review, user access review, and account provisioning/deprovisioning validation.
• Assist with phishing investigations, endpoint security events, email quarantine review, DLP alerts, and malware response.
• Participate in incident response activities, including investigation, containment, remediation, documentation, and lessons learned.
• Prepare and maintain audit evidence, control documentation, security procedures, diagrams, access review records, vulnerability reports, and incident records.
• Support customer security questionnaires, ITGC audits, supplier security reviews, cybersecurity insurance requests, and board/audit reporting as needed.
• Coordinate with internal teams and vendors to improve security operations, control maturity, and response readiness.

Qualifications

• 5+ years of experience in IT security, security administration, infrastructure security, or cybersecurity operations.
• Hands‑on experience with endpoint security, firewalls, vulnerability management, SIEM/log monitoring, MFA, Active Directory, Microsoft Entra ID, VPN, and email security.
• Ability to investigate alerts, review logs, document findings, and coordinate remediation with technical teams.
• Working knowledge of NIST CSF, CIS Controls, ISO 27001, or similar cybersecurity frameworks.
• Experience supporting audits, access reviews, security evidence collection, and remediation tracking.
• Strong communication, documentation, troubleshooting, and cross‑functional coordination skills.

Preferred Qualifications

• Experience in semiconductor, manufacturing, high‑tech, or global enterprise environments.
• Experience with Cisco FirePower, McAfee Endpoint/DLP, SecureWorks Redcloak, Imperva, Nessus, ManageEngine PAM, Proofpoint, Cisco Umbrella/OpenDNS, or similar tools.
• Experience with ITGC/SOX audits, customer security assessments, third‑party risk reviews, or cybersecurity insurance support.
• Security certifications such as Security+, CySA+, CISSP, CISM, GCIH, GCIA, Microsoft Security, or equivalent practical experience.

Alpha and Omega Semiconductor, Inc is committed to diversity in our workplace. Qualified applicants will receive consideration for employment without regard to, and will not be discriminated against based on race, age, color, ethnicity, marital status, sex, religion, national origin, sexual orientation, gender, gender identity, disability, protected veteran status or any other category protected by federal, state or local law.