{"id":3182728,"url":"https://alion.io/job/mantech-information-system-security-engineer-4","title":"Information System Security Engineer","company":{"id":179527,"name":"ManTech","domain":"mantech.com","url":"https://alion.io/company/mantech","size_band":"1001-5000","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Avature","truth_index":{"grade":"A","score":100,"open_postings":87,"ghost_share":0,"stale_share":0,"repost_share":0.011,"time_to_fill_p50_days":12,"computed_at":"2026-10-27T05:46:45Z"}},"role":"Security","role_family":"Security","seniority":"junior","employment_type":null,"work_mode":"on_site","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["Chantilly, United States"],"countries":["US"],"hiring_countries":[],"hiring_countries_total":0,"salary":{"min":91600,"max":153800,"currency":"USD","period":"year","gross":null,"usd_annual":153800},"salary_estimate":null,"experience_years_min":2,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"Bash","optional":false},{"name":"Configuration Management","optional":false},{"name":"Linux","optional":false},{"name":"Nessus","optional":false},{"name":"PowerShell","optional":false},{"name":"Python","optional":false},{"name":"RTOS","optional":false},{"name":"SIEM","optional":false},{"name":"Splunk","optional":false},{"name":"Windows","optional":false},{"name":"Chef","optional":true},{"name":"ElasticSearch","optional":true},{"name":"Kibana","optional":true}],"status":"live","first_seen_at":"2026-10-23T22:06:37Z","employer_posted_date":"2026-10-23","last_verified_at":"2026-10-27T08:40:42Z","board_verified":true,"closed_at":null,"days_open":3,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":3},"description":"Shape the future of defense with MANTECH! Join a team dedicated to safeguarding our nation through advanced tech and innovative solutions. Since 1968, we’ve been a trusted partner to the Department of Defense, delivering cutting-edge projects that make a real impact. Dive into exciting opportunities in Cybersecurity, IT, Data Analytics and more. Propel your career forward and be part of something extraordinary. Your journey starts now-protect and innovate with MANTECH!\nMANTECH seeks a motivated, career and customer-oriented Information Systems Security Engineer to join our team in Chantilly, VA. This position will be onsite. This role can optionally be in San Diego, CA.\nThe Information Systems Security Engineer (ISSE) will support Risk Management Framework (RMF), security engineering, and cybersecurity lifecycle activities. This role focuses on security control design and implementation, system hardening, technical remediation, continuous monitoring, and security stack operations, with an emphasis on Linux systems and real-time operating systems (RTOS), alongside supporting knowledge of Windows environments.\nResponsibilities include but are not limited to:\nAssist with or lead the design and integration of technical security controls into system hardware, software, and networking architectures throughout the SDLC\nWork within a technical security engineering team responsible for implementing and maintaining compliant security architectures across complex platforms\nSupport RMF execution and system categorization by defining authorization boundaries with network diagrams, hardware/software inventories, data flow documentation, and cryptographic mapping\nPerform hands-on configuration, hardening, log analysis, and remediation on Linux and RTOS environments while enforcing DISA STIGs via automated scripting\nOperate, configure, and maintain Nessus vulnerability scanners and collaborating with ISSOs to analyze scan outputs and determine remediation pathways\nDeploy, configure, and troubleshoot Trellix endpoint security tools across host endpoints to enforce strict media/device control policies and host-based defenses\nSupport and maintain enterprise log ingestion and SIEM platforms such as Splunk or Elastic (ELK) to support centralized auditing and continuous monitoring\nMaintain accurate RMF artifacts in eMASS, including the System Security Plan (SSP), POA&M, and supporting technical evidence to support Authorizing Official (AO) decisions\nMinimum Qualifications:\nBachelor’s degree in IT, Computer Science, Cybersecurity, Computer Engineering, or related field with 2+ years of relevant cybersecurity, system administration or RMF experience; OR High School Diploma/GED with 6+ years of cybersecurity engineering, system administration, or RMF experience\n2+ years of hands-on experience configuring, hardening, or troubleshooting Linux operating systems, with exposure to RTOS (e.g., QNX, VxWorks) or Windows environments\nActive DoD 8570/8140 IAT Level II certification, e.g., CompTIA Security+ CE, CySA+, SecurityX, CISSP\nHands-on experience or working knowledge of Nessus vulnerability scanners and Trellix endpoint security tools\nExperience or training with eMASS \nFamiliarity with scripting languages (Bash, Python, or PowerShell) for basic task automation, configuration management, or compliance checking\nPreferred Qualifications:\nHands-on experience installing, configuring, or operating Splunk, Elasticsearch/Kibana (ELK), or another enterprise log analytics platform\nUnderstanding of PL2 vs. PL3 security baselines, trust boundaries, and segmentation concepts\nActive industry certifications such as CompTIA Linux+, CGRC, or IAT Level III SecurityX (CASP+), or CISSP\nExperience integrating security into the SDLC or utilizing configuration management tools (Ansible, Puppet, Chef) for STIG automation\nClearance Requirements:\nMust have a current or active Top Secret security clearance\nPhysical Requirements:\nMust be able to remain in a stationary position 50% of the time\nNeeds to occasionally move about inside the office to access file cabinets, office machinery, etc.\nFrequently communicates with co-workers, management, and customers, and must be able to exchange accurate information in these situations\nThe projected compensation range for this position is $91,600.00-$153,800.00. There are differentiating factors that can impact a final salary/hourly rate, including, but not limited to, Contract Wage Determination, relevant work experience, skills and competencies that align to the specified role, geographic location (For Remote Opportunities), education and certifications as well as Federal Government Contract Labor categories. In addition, MANTECH invests in its employees beyond just compensation. MANTECH’s benefits offerings include, dependent upon position, Health Insurance, Life Insurance, Paid Time Off, Holiday Pay, short-term and long-term Disability, Retirement and Savings, Learning and Development opportunities, wellness programs as well as other optional benefit elections.\nMANTECH considers all qualified applicants for employment without regard to disability or veteran status or any other status protected under any federal, state, or local law or regulation.\nIf you need a reasonable accommodation to apply for a position with MANTECH, please email us at  and provide your name and contact information.","description_format":"text","description_chars":5395,"description_truncated":false,"requirements":{"experience_years_min":2,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"high_school","optional":false},"security_clearance":true,"languages":[]},"benefits":["Health insurance","Life insurance","Wellness"],"hiring_locations":[{"name":"United States","iso":"US","kind":"country"}],"hiring_excludes":[],"relocation_offered":false,"industries":["National Security","Information Security","IT Consulting & Digital Transformation"],"lifecycle":[{"event":"open","at":"2026-10-23T22:06:37Z"}],"visa":[],"liveness":{"score":90,"band":"hot","label":"Hiring now","p_open":1,"p_active":0.903,"p_room":1,"age_days":3,"expected_fill_days":12,"reasons":["conf:1","velocity","win:early","comp:junior,brand"],"computed_at":"2026-10-27T05:46:45Z"},"pay":{"stated_usd_annual":153800,"is_top_pay":true},"html_url":"https://alion.io/job/mantech-information-system-security-engineer-4","json_url":"https://alion.io/job/mantech-information-system-security-engineer-4.json","meta":{"generated_at":"2026-10-27T11:48:17Z","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":14006,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-28T00:00:00Z"}},"offers":[{"id":"company.slices","title":"One company in depth, by slice","status":"live","price":{"credits":0.02,"usd":0.002,"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":179527},"rest":"https://alion.io/mcp/rest/get_company?id=179527"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fmantech-information-system-security-engineer-4"},{"id":"market.stats","title":"A market slice: pay, demand and time to fill","status":"live","price":{"credits":1,"usd":0.1},"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%2Fmantech-information-system-security-engineer-4"},{"id":"job.search","title":"Open jobs by role, technology, place, pay and visa","status":"live","price":{"credits":0.02,"usd":0.002},"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%2Fmantech-information-system-security-engineer-4"},{"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/mantech-information-system-security-engineer-4\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fmantech-information-system-security-engineer-4"}]}