Offensive Security Engineer – Pentesting, DevSecOps

Klar

. Own end-to-end penetration testing engagements across Klar's web applications, APIs, and backend services, from identifying vulnerabilities to validating remediation .

Posted 11/11/2026full-timeRemote • ArgentinaMid-LevelSeniorWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates expertise in manual penetration testing of web applications, APIs, and backend services, with a strong understanding of OWASP standards and a proactive approach to security automation. Capable of collaborating effectively with engineering teams to remediate vulnerabilities and improve security practices in a fintech environment.

Highest-signal resume keywords

Manual Penetration TestingOWASP Top 10Burp SuiteDevSecOpsAWS Security

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

Penetration TestingVulnerability IdentificationSource Code ReviewScripting with PythonScripting with BashSecurity AssessmentRisk AssessmentContinuous ImprovementAutomation SkillsExploit Development

Soft Skills

Effective CommunicationTechnical CuriosityProactive ApproachCollaborationOwnership

Tools & Technologies

Burp SuiteGitHubDockerKubernetesTerraformSemgrepSnykSonarQubeCheckmarxCI/CD Pipelines

Certifications & Qualifications

OSCPOSWEEWPTX

Industry Keywords

FintechBankingFinancial ServicesSecurity-by-DesignVulnerability Research

Tech Stack

Tools & technologies

AWSCloudDockerKubernetesPythonSDLCTerraform

About the role

Key responsibilities & impact

Own end-to-end penetration testing engagements across Klar's web applications, APIs, and backend services, from identifying vulnerabilities to validating remediation
Work on security challenges in a fintech environment, protecting financial products, sensitive customer data, and critical business operations
Conduct in-depth manual security assessments beyond automated scanning
Explore attack scenarios and identify vulnerabilities automated tools may miss
Collaborate with engineering teams to explain security findings and assess potential impact
Help design practical, sustainable remediation solutions
Share offensive security insights to support security-by-design and earlier vulnerability prevention
Improve security testing through automation, testing methodologies, and continuous process improvements
Influence security practices with meaningful ownership and autonomy

Requirements

What you’ll need

Proven experience performing manual penetration testing on web applications, REST APIs, and backend services
Strong understanding of OWASP Top 10 and OWASP API Security Top 10
Hands-on experience identifying and exploiting authentication, authorization, IDOR/BOLA, SSRF, injection, and business logic vulnerabilities
Advanced proficiency with Burp Suite and offensive security tools
Ability to review source code and identify security vulnerabilities
Practical knowledge of DevSecOps, CI/CD pipelines, and Secure SDLC practices
Familiarity with SAST, DAST, and SCA security tools
Experience with GitHub, GitHub Actions, or similar CI/CD platforms
Scripting and automation skills using Python or Bash
Experience collaborating with software engineers to remediate vulnerabilities
AWS and Cloud Security experience
Knowledge of Docker, Kubernetes, and Terraform
Experience with Semgrep, Snyk, SonarQube, Checkmarx, or similar tools
Participation in Bug Bounty programs, CTF competitions, or vulnerability research
Certifications such as OSCP, OSWE, eWPTX, or equivalent
Previous experience in fintech, banking, or financial services
Strong offensive security mindset and technical curiosity
Ability to independently conduct end-to-end penetration testing engagements
Experience demonstrating the real-world impact of security vulnerabilities
Strong risk assessment and prioritization skills
Effective communication with engineering teams
A proactive approach to security automation and continuous improvement

Benefits

Comp & perks

Competitive salary based on performance and experience
Chance of earning Klar stock options
26 days of paid vacation per year
Computer devices
Sponsored coaching and therapy sessions via Mantra Care
International work environment with amazing and highly skilled people
A world class team that helps you evolve your skills in areas you're interested in
Safe, welcoming, diverse, and inclusive environment