Information System Security Officer (ISSO)

TEKsystems is seeking an Information Systems Security Officer (ISSO) with a Top Secret Clearance in Richardson, TX in support of a Secure Development Environment (SDE) Infrastructure Deployment to support classified and controlled engineering workloads associated with Department of Defense (DoD) programs., This project is projected to be 12 months in duration and will include a one time 30 day CONUS travel assignment for a deployment., We are seeking an Information Systems Security Officer (ISSO) to support the security posture and compliance operations of our infrastructure program across classified and unclassified environments. Working closely with the ISSE and program leadership, you will serve as the day-to-day security operations authority - monitoring system compliance, maintaining RMF documentation, coordinating vulnerability remediation, and acting as the primary point of contact for security-related activities on the program. This is a critical role for a security professional who thrives in a structured, compliance-driven environment and wants to make a direct impact on mission-critical defense systems.

What You’ll Do -Serve as the designated ISSO for assigned information systems, maintaining responsibility for the day-to-day security posture and compliance of those systems -Support the RMF process including maintaining System Security Plans (SSPs), POA&Ms, and other ATO documentation in coordination with the ISSE -Monitor systems for security compliance, configuration drift, and policy violations, escalating findings to the ISSE and program leadership as appropriate -Coordinate and track vulnerability management activities including scan scheduling, findings review, remediation tracking, and reporting -Conduct and support STIG compliance reviews across infrastructure components including servers, network devices, operating systems, and applications -Support continuous monitoring activities and ensure ongoing adherence to ATO conditions and security control requirements -Serve as the primary security point of contact for day-to-day interactions with government ISSMs, security control assessors, and authorizing official representatives -Assist with security incident identification, reporting, and response activities in accordance with program and government requirements -Conduct user security awareness activities and enforce program-specific security policies and procedures -Maintain accurate and current security documentation including system inventories, access control records, and audit logs

5-7+ years of experience in an ISSO, security operations, or information assurance role supporting DoD or cleared defense contractor programs -Working knowledge of the RMF process including ATO documentation requirements and interaction with government security stakeholders -Solid understanding of NIST 800-53 security controls and DISA STIGs across common infrastructure platforms -Experience supporting vulnerability management programs using tools such as Nessus, ACAS, or equivalent scanning platforms -Familiarity with SIEM platforms and security event monitoring in classified environments -Strong attention to detail and ability to manage multiple compliance workstreams simultaneously -Active Top Secret security clearance required; TS/SCI eligibility preferred -Security+ or equivalent DoD 8570/8140 IAT Level II certification required; CISSP or CASP+ a strong plus, Prior experience serving as a designated ISSO on a DoD or IC program -Familiarity with eMASS or equivalent RMF management tools -Experience supporting programs at the TS/SCI or SAP/SAR level -Knowledge of JSIG, ICD 503, or IC-specific security requirements -Familiarity with cross-domain solutions and data transfer requirements in classified environments -Bachelor’s degree in Cybersecurity, Information Technology, Computer Science, or a related field; equivalent experience considered -DoD 8570/8140 IAT Level II or III certification (Security+, CASP+, CISSP, or equivalent)