Cloud Security Administrator - RHEL

Leidos • Adelphi, MD

5d • Hybrid

About The Position

Leidos is seeking a Cloud Security Administrator with senior-level Red Hat Enterprise Linux (RHEL) administration experience to support the U.S. Army C5ISR Cyber Security Service Provider (CSSP). The role helps secure and sustain AWS cloud environments by administering security controls, identifying vulnerabilities, coordinating remediation, and supporting continuous compliance monitoring. The administrator collaborates with cloud engineers, cybersecurity specialists, and mission partners to strengthen cloud security, streamline remediation, and maintain operational readiness across enterprise environments.

The position is based in Adelphi, Maryland, with a hybrid schedule requiring three days onsite. U.S. citizenship and an active Secret clearance are required at the start; TS/SCI is required for the position, subject to program access and eligibility requirements. The employee must meet applicable DoD 8140 qualification requirements at the start and obtain required CSSP and Computing Environment certifications within 90 days, as applicable to the assigned work role.

Requirements

• Bachelor's degree with 8 or more years of relevant experience, or a master's degree with 4 or more years of relevant experience; additional relevant experience may be considered in lieu of a degree.
• Hands-on experience administering security controls in AWS or other enterprise cloud environments.
• Working knowledge of AWS security services, including IAM, CloudTrail, CloudWatch, Security Hub, GuardDuty, Systems Manager, KMS, and VPC security controls.
• Experience with vulnerability management, security assessments, compliance monitoring, patch management, and remediation tracking.
• Demonstrated hands-on experience administering RHEL systems in production or enterprise environments.
• Familiarity with Linux and Windows security administration, including host-level and cloud security findings.
• Experience using Ansible to automate routine system-administration tasks, such as configuration changes, account management, and compliance remediation.
• Understanding of DoD cybersecurity requirements, RMF/ATO, NIST SP 800-53, and DISA STIG/SRG standards.
• Experience with SIEM, endpoint security, enterprise logging, security monitoring, and ticketing platforms.
• Strong analytical, troubleshooting, documentation, and communication skills.
• Ability to meet applicable DoD 8140 qualification requirements at the start and obtain required CSSP and Computing Environment certifications within 90 days, as applicable to the assigned work role.
• U.S. citizenship and an active Secret security clearance required at the start; TS/SCI required for the position, subject to program access and eligibility requirements.

Nice To Haves

• Experience securing DoD cloud environments, including AWS GovCloud, IL4/IL5/IL6, Cloud One, or ECMA.
• Hands-on experience with Tenable.sc/ACAS, Elastic Security, Elastic Agent Defend, AWS Security Hub, or GuardDuty.
• Experience supporting RMF authorization packages, ATO assessments, and continuous-monitoring compliance activities.
• DoD 8140-aligned certification, such as CISSP, or an equivalent certification appropriate to the assigned work role.
• AWS cloud or security certification and familiarity with scripting, automation, or infrastructure as code.

Responsibilities

• Administer, monitor, and maintain cloud security controls across AWS 2.0 and CSSP subscriber environments.
• Diagnose and resolve Linux operating-system, service, storage, networking, authentication, and application issues.
• Identify, assess, track, and coordinate remediation of cloud vulnerabilities, misconfigurations, and compliance findings.
• Manage AWS security capabilities, including IAM, CloudTrail, CloudWatch, Security Hub, GuardDuty, KMS, and VPC security controls.
• Support Risk Management Framework (RMF), Authorization to Operate (ATO), and continuous monitoring through security assessments, control validation, and compliance documentation.
• Conduct security configuration reviews across AWS resources, Linux and Windows systems, and supporting cloud infrastructure.
• Support onboarding of CSSP subscribers into centralized logging, vulnerability management, Elastic Agent Defend, and other security services.
• Coordinate security patching, access reviews, change management, incident response, and ongoing security operations.
• Develop and maintain security procedures, operational runbooks, compliance evidence, and technical documentation.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior