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# Penetration Tester III

- **Company:** The Sos
- **Location:** Washington, DC, United States
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Software System Penetration Testing, Open Web Application Security, Red Team (Cyber Security), Strategies of Testing, Software Vulnerability Management, Cloud Platform System, Mitre Att&ck, Cyber Warfare
- **Published:** October 23, 2026
- **Apply:** https://www.dcjobsite.com/job.asp?id=3466648911&tx=JP2721FFG&pt=1&aff=0B19D771-A501-4A5E-8338-2A822B784D54&utm_source=Job%20Feed&utm_medium=textkernel&utm_campaign=DE&utm_term=0B19D771-A501-4A5E-8338-2A822B784D54

## About the Role

* Experience:
 * Five (5) to seven (7) years of penetration testing experience
 * Management or team lead experience
 * Experience performing continuous penetration testing
 * Experience conducting red team operations
 * Experience performing IoT, mobile, and cloud penetration testing
 * Experience supporting High Value Asset (HVA) assessments
 * Experience applying MITRE ATT&CK, OSSTMM, OWASP, NIST, PTES, and ISSAF methodologies
 * Education:
 * Bachelor's Degree
 * Certifications: Required:
 * GPEN or GXPN
 * CISA AES HVA Lead or Technical Lead , or ability to obtain
 * Plus one of the following:
 * GRTP
 * CRTL
 * OSCP
 * CRTP
 * CMWAPT
 * CEPT
 * CPT
 * LPT
 * Clearance/Suitability : Secret (active)

## Description

SOSi is seeking a Penetration Tester III to support proactive cyber defense activities in alignment with our customer. This role is responsible for conducting penetration testing and red team activities, assessing security posture across enterprise environments, and supporting identification, validation, and reporting of vulnerabilities to improve cyber defense resilience., * Conduct penetration testing across enterprise systems, applications, and network environments

 * Perform red team activities to evaluate security controls and identify exploitable weaknesses
 * Support continuous penetration testing activities to assess evolving threats and vulnerabilities
 * Conduct testing of IoT, mobile, and cloud environments
 * Support High Value Asset (HVA) security assessments
 * Apply testing methodologies and frameworks including MITRE ATT&CK, OSSTMM, OWASP, NIST, PTES, and ISSAF
 * Identify, document, validate, and report vulnerabilities and recommended remediation actions
 * Support cyber defense operations through coordination with security engineering, vulnerability management, and incident response teams