{"id":3556817,"url":"https://alion.io/job/caci-international-information-systems-security-engineer-isse-linuxrhel","title":"Information Systems Security Engineer (ISSE) Linux/RHEL","company":{"id":58481,"name":"CACI International","domain":"caci.com","url":"https://alion.io/company/caci-international","size_band":"5000+","is_staffing_agency":false,"employer_type":"services","is_intermediary":false,"listed_via":null,"ats_vendor":"Workday","truth_index":{"grade":"D","score":50,"open_postings":342,"ghost_share":0.579,"stale_share":0.181,"repost_share":0.699,"time_to_fill_p50_days":47,"computed_at":"2026-11-15T07:52:55Z"}},"role":"Security","role_family":"Security","seniority":"junior","employment_type":"full_time","work_mode":"on_site","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["Sterling, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":86600,"max":181800,"currency":"USD","period":"year","gross":null,"usd_annual":181800},"salary_estimate":null,"experience_years_min":2,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"Ansible","optional":false},{"name":"Bash","optional":false},{"name":"Git","optional":false},{"name":"GitLab","optional":false},{"name":"Linux","optional":false},{"name":"Nessus","optional":false},{"name":"NIST 800-53","optional":false},{"name":"Puppet","optional":false},{"name":"Python","optional":false},{"name":"Red Hat","optional":false}],"status":"live","first_seen_at":"2026-10-29T00:00:00Z","employer_posted_date":"2026-10-29","last_verified_at":"2026-11-15T02:48:10Z","board_verified":true,"closed_at":null,"days_open":17,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":17},"description":"Job Title: Information Systems Security Engineer (ISSE) Linux/RHELJob Category: SecurityTime Type: Full timeMinimum Clearance Required to Start: TS/SCIEmployee Type: RegularPercentage of Travel Required: Up to 25%Type of Travel: Continental US* * * The Opportunity:\nWe are seeking a highly motivated, Linux-focused Information Systems Security Engineer (ISSE) to support the security, accreditation, and continuous monitoring of mission-critical systems operating within classified environments.\nThe ideal candidate combines cybersecurity engineering expertise with hands-on Red Hat Enterprise Linux (RHEL) administration skills. This position requires an individual comfortable working directly with Linux systems to implement security controls, troubleshoot configurations, remediate vulnerabilities, and support Risk Management Framework (RMF) compliance.\nWorking alongside systems engineers, software developers, and cybersecurity professionals, you will help design, implement, and maintain secure solutions supporting critical national security missions.\nThis position requires onsite support 100% of the time in Sterling, VA. Domestic and international travel opportunities may be available.\nResponsibilities:\nPerform hands-on security engineering, configuration, troubleshooting, and hardening of Red Hat Enterprise Linux (RHEL) systems\nImplement, validate, and maintain DISA STIG compliance, including executing SCAP scans, analyzing findings, and remediating security vulnerabilities\nTroubleshoot Linux security configurations involving SELinux, SSH, permissions, authentication, system services, and networking\nLead and support Assessment and Authorization (A&A) activities to achieve and maintain Authorization to Operate (ATO) under the Risk Management Framework (RMF)\nDevelop and maintain security documentation, including System Security Plans (SSPs), Security Assessment Reports (SARs), Security Control Traceability Matrices (SCTMs), and Plans of Action and Milestones (POA&Ms)\nConduct security assessments and continuous monitoring activities aligned with ICD 503, NIST 800-53, CNSSI, and applicable DoD requirements\nCollaborate with systems, network, software, and DevOps engineers to integrate security requirements throughout the System Development Life Cycle (SDLC)\nEvaluate system architectures, infrastructure changes, and software configurations to identify security risks and recommend mitigations\nDevelop Bash or Python scripts to automate security compliance, vulnerability assessments, and routine administrative tasks.\nQualifications:\nRequired: \nRequired\n5+ years of combined experience in cybersecurity engineering, information assurance, Linux systems administration, or related technical disciplines\nMinimum 2 years of hands-on Linux administration experience, preferably with RHEL 8/9\nPractical Linux command-line proficiency, including filesystem management, permissions, user administration, package management (DNF/YUM), systemd services, log analysis, SSH, and basic network troubleshooting\nExperience implementing Linux DISA STIGs, executing SCAP scans, and performing vulnerability remediation\nWorking knowledge of Linux security technologies, including SELinux, firewalld, authentication, and access controls\nExperience with Bash scripting and/or Python for system administration or security automation\nStrong understanding of RMF, ICD 503, NIST 800-53, and the ATO lifecycle\nDoD 8570/8140 IAT Level II certification (Security+ CE, CySA+, SSCP, or equivalent applicable certification)\nBachelor's degree in a technical discipline or equivalent relevant experience\nActive Top Secret clearance with SCI eligibility.\nDesired:\nRed Hat Certified System Administrator (RHCSA) or Red Hat Certified Engineer (RHCE) certification.\nExperience supporting RHEL systems in classified, disconnected, or air-gapped environments.\nFamiliarity with Puppet, Ansible, Red Hat Satellite, or Red Hat Identity Management (IdM/FreeIPA).\nExperience with ACAS, Nessus, SCAP Compliance Checker, or similar vulnerability assessment tools\nExperience with Git, GitLab, DevSecOps, and automated compliance solutions\nExperience supporting Cross Domain Solutions (CDS) or other highly secure mission systems\nAdvanced cybersecurity certifications such as CISSP or CASP+\n-What You Can Expect:\nA culture of integrity.\nAt CACI, we place character and innovation at the center of everything we do. As a valued team member, you’ll be part of a high-performing group dedicated to our customer’s missions and driven by a higher purpose - to ensure the safety of our nation.\nAn environment of trust.\nCACI values the unique contributions that every employee brings to our company and our customers - every day. You’ll have the autonomy to take the time you need through a unique flexible time off benefit and have access to robust learning resources to make your ambitions a reality.\nA focus on continuous growth.\nTogether, we will advance our nation's most critical missions, build on our lengthy track record of business success, and find opportunities to break new ground - in your career and in our legacy.\nPay Range:\nThere are a host of factors that can influence final salary including, but not limited to, geographic location, Federal Government contract labor categories and contract wage rates, relevant prior work experience, specific skills and competencies, education, and certifications. Our employees value the flexibility at CACI that allows them to balance quality work and their personal lives. We offer competitive compensation, benefits and learning and development opportunities. Our broad and competitive mix of benefits options is designed to support and protect employees and their families. At CACI, you will receive comprehensive benefits such as; healthcare, wellness, financial, retirement, family support, continuing education, and time off benefits.\nThe proposed salary range for this position is:\n$86,600 - $181,800CACI is an Equal Opportunity Employer.All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, pregnancy, sexual orientation, age, national origin, disability, status as a protected veteran, or any other protected characteristic.","description_format":"text","description_chars":6227,"description_truncated":false,"requirements":{"experience_years_min":2,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"bachelor","optional":false},"security_clearance":true,"languages":[]},"benefits":["Flexible time off"],"hiring_locations":[{"name":"United States","iso":"US","kind":"country"}],"hiring_excludes":[],"relocation_offered":false,"industries":["Cybersecurity","Data & Analytics","Military","Information Security"],"lifecycle":[{"event":"open","at":"2026-10-31T01:16:16Z"}],"visa":[],"liveness":{"score":63,"band":"ok","label":"Likely open","p_open":1,"p_active":0.695,"p_room":0.9,"age_days":17,"expected_fill_days":47,"reasons":["conf:5","stale_co","urgency","velocity","win:mid","comp:junior,brand"],"computed_at":"2026-11-15T07:52:55Z"},"pay":{"stated_usd_annual":181800,"is_top_pay":true},"html_url":"https://alion.io/job/caci-international-information-systems-security-engineer-isse-linuxrhel","json_url":"https://alion.io/job/caci-international-information-systems-security-engineer-isse-linuxrhel.json","meta":{"generated_at":"2026-11-15T18:21:03Z","cache_seconds":300,"methodology":"https://alion.io/methodology","terms":"https://alion.io/terms","contact":"https://alion.io/contact","api":"https://alion.io/developers","about":"Alion is a live layer of people, companies and AI agents: who they are, whether they are real and active right now, what they do and how to work with them, readable by people and by agents and paid per call.","catalog":"https://alion.io/catalog.json","usage":{"tier":"crawler_verified","counted_by":"address","units_charged":1,"used_today":11155,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-11-16T00:00:00Z"}},"offers":[{"id":"company.slices","title":"One company in depth, by slice","status":"live","price":{"credits":0.1,"usd":0.01,"plus_per_slice":{"credits":0.05,"usd":0.005}},"unit":"per company, plus each slice with data","note":"the employer in depth","call":{"mcp_tool":"get_company","arguments":{"id":58481},"rest":"https://alion.io/mcp/rest/get_company?id=58481"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fcaci-international-information-systems-security-engineer-isse-linuxrhel"},{"id":"market.stats","title":"A market slice: pay, demand and time to fill","status":"free","price":{"credits":0,"usd":0},"unit":"per slice","note":"pay, demand and time to fill for this role and place","call":{"mcp_tool":"market_stats"},"human":"https://alion.io/catalog?offer=market.stats&for=job%2Fcaci-international-information-systems-security-engineer-isse-linuxrhel"},{"id":"job.search","title":"Open jobs by role, technology, place, pay and visa","status":"live","price":{"credits":0.1,"usd":0.01},"unit":"per posting in a list","note":"similar open postings","call":{"mcp_tool":"search_jobs"},"human":"https://alion.io/catalog?offer=job.search&for=job%2Fcaci-international-information-systems-security-engineer-isse-linuxrhel"},{"id":"company.verify","title":"Is this company real and active right now","status":"pilot","price":null,"unit":"per company","request":{"url":"https://alion.io/catalog/request","method":"POST","body":"{\"offer\": \"company.verify\", \"for\": \"job/caci-international-information-systems-security-engineer-isse-linuxrhel\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fcaci-international-information-systems-security-engineer-isse-linuxrhel"}],"agent":{"mcp":"https://alion.io/mcp/jobs","mcp_open":"https://alion.io/mcp/open","next":[{"tool":"get_job","arguments":{"id":3556817}},{"tool":"search_jobs","arguments":{"company":"caci.com","detail":"compact"}},{"tool":"match_people","arguments":{"job_id":3556817},"note":"people open to offers who fit this vacancy"}],"note":"The same data through MCP tools: https://alion.io/mcp/open needs no sign-in (compact searches, postings, people); https://alion.io/mcp with an Alion account has everything. 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