[Hiring] Senior Security Specialist – Penetration Testing @LSEG

Role Description

LSEG is seeking a Senior Penetration Tester to join our internal offensive security team. This role is hands-on and deeply technical, responsible for planning and executing penetration tests across a wide range of systems and applications. The successful candidate will be a skilled offensive security professional with a passion for uncovering vulnerabilities and improving security posture through rigorous testing and collaboration.

• Conduct in-depth penetration tests on applications, infrastructure, and cloud environments.
• Take full ownership of assigned pentesting engagements end-to-end and deliver with limited oversight.
• Compile technical scoping documents, track and document assessment metadata including:
  • Engagement details (who, what, when, where)
  • Testing team members and roles
  • Tools and methodologies used
  • Schedule and timelines
  • Target systems and environments
  • Constraints, exclusions, and limitations
  • Testing activities and event logs
• Document findings clearly and concisely, providing actionable remediation guidance.
• Collaborate with application teams to scope, execute, and report on security assessments.
• Contribute to team improvement efforts and ensure all initiatives and feedback are well documented for future references.
• Contribute to the continuous improvement of testing methodologies, tooling, and automation.
• Stay current with emerging threats, vulnerabilities, and offensive security techniques.
• Participate in R&D initiatives as guided from leadership.
• Support knowledge sharing and mentoring within the team.
• Develop and maintain custom tools, scripts, and exploits to support testing activities.

Qualifications

• Proven hands-on experience in penetration testing of Web Applications, APIs, Thick Client and Common Infrastructures (Active Directory, Cloud and Cloud-native based environments).
• Proficiency with tools such as Burp Suite, common command-line tools, and ability to write custom scripts when needed.
• Experience in automating pentesting tasks.
• Strong understanding of application security, network protocols, and operating systems.
• Experience with cloud platforms (AWS, Azure, GCP) and containerized environments (Docker, Kubernetes).
• Ability to write clear, technical reports and communicate findings to both technical and non-technical stakeholders.
• Experience working in large, complex enterprise environments.
• Fluent communication skills in English, both written and verbal.
• Relevant certifications and engagement with the security community is a plus.
• Threat Modelling experience is a plus.
• Proven track record of successfully managing and executing security engagements for various organizations with differing operational and technical profiles.
• Ability to identify, assess, and communicate technical and project risks to stakeholders.
• Understanding project requirements and aligning deliverables with agreed upon objectives and timelines.

Benefits

• Healthcare
• Retirement planning
• Paid volunteering days
• Wellbeing initiatives