​​Information Systems Security Engineer

Job Description

Description

​​The Multi-Domain Solutions Division at Leidos currently has an opening for a Secret cleared Information Systems Security Engineer (ISSE) to work in our Orlando, Florida office. Ability to work in Central Florida is preferred.

​Primary Responsibilities

​The ISSE will be responsible for monitoring TEMPEST certifications and the development of an RMF Assess and Authorize (A&A) package, including detailing controls, a system scanning plan, POA&M maintenance, and a Body of Evidence validating control implementation. High Level tasking for this team will include the following :

​Build and support a culture grounded in the Leidos values, beliefs and expectations and highest standards of ethical and respectful behavior

​Plan and detail the security of a complex mission-critical defense network per the DoD RMF

​Plan, document, and achieve system Interim Authorization to Test (IATT), Interim Authorization to Operate (IATO), Authorization to Operate (ATO), Authorization to Connect (ATC), Interconnection Security Agreement (ISA) and other approvals as required by the Government Authorizing Official

​Perform and / or review security assessments of computing environments to identify points of vulnerability, non- compliance with established Cybersecurity standards and regulations and recommend mitigation strategies.

​Validate and verify system security requirements definitions and analysis.

​Assist architects and systems developers in the identification and implementation of appropriate information security functionality to ensure uniform application of security policy and solutions.

​Assess and develop mitigations for system security threats / risks throughout the program life cycle.

​Contribute to the security planning, assessment, risk analysis, risk management, certification and awareness activities for system and networking operations.

​Basic Qualifications

​Must possess a minimum of a Secret clearance with the ability to obtain and maintain a TS / SCI clearance.

​A Bachelors Degree and 8-12 years of relative experience.

​Achievement of any DoD 8140 or DoD 8570 baseline certification within 6 months of start of work .

​Experience with the NIST Risk Management Framework

​Experience with NIST SP 800-53 control development and documentation

​Ability to achieve a high degree of customer satisfaction and maintain Leidos positive brand recognition

​Ability to work with a distributed team

​Preferred Qualifications

​Experience working with DoD security Assessment and Authorization

​Experience with eMASS

​Experience with Jira

​Experience with Confluence

​Experience developing and maintaining authorization Body of Evidence

​Experience with Tenable Nessus

​Experience with Security Onion SIEM solution

​Understanding of TEMPEST requirements and assessments  ​

At Leidos, we don’t want someone who "fits the mold"—we want someone who melts it down and builds something better. This is a role for the restless, the over-caffeinated, the ones who ask, “what’s next?” before the dust settles on “what’s now.”

If you’re already scheming step 20 while everyone else is still debating step 2… good. You’ll fit right in.

Original Posting : October 24, 2025

For U.S. Positions : While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.

Pay Range : Pay Range $104,650.00 - $189,175.00

The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.