Senior Offensive Security Consultant – Adversary Emulation

Grant Thornton; Chicago (IL); Hybrid; USD 140,000 - 190,000; Full time

Benefits offered by this job

Discretionary annual bonus

Hybrid work model

Comprehensive benefits

Reasonable accommodation available

Job summary

Grant Thornton is seeking a Senior Offensive Security Consultant to lead adversarial testing engagements across industries. You will simulate real-world attackers, validate detections, and help clients strengthen their security posture through actionable reporting and executive communications.

The role demands hands-on penetration testing across networks, apps, and cloud, with strong collaboration to mature client security programs and contribute to methodology and tooling in a hybrid work

Qualifications

• Bachelor’s degree in Cybersecurity, IT, CS or related field
• 3+ years of hands-on offensive security, pentesting, or red teaming
• Expertise across network, application, cloud, and internal infrastructure testing
• Strong understanding of adversary TTPs and frameworks such as MITRE ATT&CK, ATLAS and OWASP
• Proficiency with industry-standard tooling and command‑and‑control frameworks
• Scripting and automation skills (Python, PowerShell, Bash)
• Experience conducting assume‑breach or adversary emulation engagements
• Excellent written and verbal communication skills for professional, client‑ready reports
• Ability to work independently, manage multiple engagements, and meet deadlines in a client-service environment

Responsibilities

• Penetration Testing: plan and execute network, app, API, and cloud tests from scoping to reporting
• Adversary Emulations: design and run threat-informed attack simulations
• Assume‑Breach: conduct assume‑breach engagements with defensive teams
• AI Red Teaming: test AI/ML systems and LLM-enabled apps, including prompt injection
• Threat Emulation: map TTPs to MITRE ATT&CK
• Reporting & Communication: deliver clear, prioritized remediation guidance to executives
• Client Advisory: act as trusted technical advisor on risk and remediation
• Practice Development: contribute to methodology, tooling, automation, and mentor juniors

Skills

Penetration testing

Adversary emulation

Threat emulation

MITRE ATT&CK

OWASP

Python

PowerShell

Bash

Communication

Self-driven

Education

Bachelor's degree in Cybersecurity / IT / CS

Tools

Metasploit

Burp Suite

Cobalt Strike

Nessus

Nmap

Job description

Grant Thornton is seeking a Senior Offensive Security Consultant to lead adversarial testing engagements across industries. You will simulate real-world attackers, validate detections, and help clients strengthen their security posture through actionable reporting and executive communications.

The role demands hands-on penetration testing across networks, apps, and cloud, with strong collaboration to mature client security programs and contribute to methodology and tooling in a hybrid work