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Alejandro PerezAP

Alejandro Perez

Supermalter

Cyber Security Expert

€450/day
3 projects
Barcelona, ES
15+ years

Average response time: 1 hour

About Alejandro

Information Security professional with 20+ years of hands-on experience covering the full security spectrum: from penetration testing and security audits to cloud security architecture, incident response, and AI-driven automation.

I work with organizations across regulated industries — fintech, electoral technology, critical infrastructure, and banking — helping them build, operate, and mature their security programs. My engagements range from short-term technical assessments to long-term embedded security operations roles.

What I do:
On the offensive and assessment side, I design and execute penetration testing programs, conduct ethical hacking engagements (OWASP/OSSTMM), perform cloud security assessments (Azure and AWS), manage vulnerability lifecycle programs, and deliver audit-ready security documentation for ISO 27001 and PCI DSS cycles. I've assessed critical national infrastructure including digital voting system.

On the detection and response side, I build production-grade SIEM deployments in Microsoft Sentinel — KQL detection rules, SOAR playbooks in Azure Logic Apps and n8n, threat hunting workflows, and incident response as escalation point.

On the cloud architecture side, I design and implement security frameworks across Azure (Sentinel, Defender XDR, Entra ID, Conditional Access, Intune, Purview, Key Vault, AKS, Front Door) and AWS (GuardDuty, CloudTrail, Security Hub, Inspector, IAM, WAF, Config, EventBridge). I've built Zero Trust architectures, automated telemetry pipelines, and governed MSSP relationships for multi-cloud regulated environments.

I also cover email security (SPF, DKIM, DMARC implementation and migration), MDM and PKI, security awareness programs, and policy and standards development.

I automate everything possible — Python, PowerShell, KQL, and API integrations.

Certifications: CISM · AWS Security Specialty · AWS Solutions Architect · ISO 27001 Lead Implementer · PMP · CCSP · ISC2 CC · ITIL ·
  • Spanish

    Native or bilingual

  • English

    Fluent

Remote only
Primarily works remotely

Experience

  • Dmarcdefense
    Co-Founder
    TECH
    February 2019 - Today (7 years and 4 months)
    Barcelona, Spain
    As the founder at DmarcGuardian I specialize in providing managed DMARC services to help organizations improve their email security and deliverability. With a strong background in cloud services and a passion for innovative cybersecurity solutions, I've dedicated my time to empowering businesses to protect their digital assets and reputation.

    At DmarcGuardian, we offer a comprehensive suite of managed DMARC services, including policy setup, monitoring, reporting, and ongoing optimization. Our team of dedicated professionals works tirelessly to ensure that our clients' email infrastructure is resistant to phishing attacks, spoofing, and other malicious activities.

    In my role, I oversee the development of cutting-edge features and tools to enhance our service offerings while also leading our managed services team to deliver exceptional support and results for our clients. My expertise in email security, DMARC, and features development, combined with my commitment to customer success, enables me to drive DmarcGuardian toward becoming a leading provider of managed DMARC services.

    Specialties: DMARC, Email Security, Managed Services, Software Development, Cybersecurity, Phishing Prevention, Email Deliverability, and Team Leadership.
    Ciberseguridad Cloud Security AWS Security Azure Security PenTest
  • Cybersec Corp
    Founder
    June 2017 - Today (9 years)
    Cyber security services:
    - Read team exercises
    - Penetration test
    - Phishing exercise
    - Forensic analysis
    - Cloud security
  • Bigfinite Inc.
    Cyber Security Manager
    August 2018 - July 2019 (11 months)
    Barcelona, Spain

Reviews

5.0

Out of 1 rating

J

Javier

Sogeti part of Capgemini - Spain

Reviewed on 3/17/2025

Gran profesional!! el cliente con el trabaja está muy satisfecho con us trabajo. Es un profesional con el que trabajaría siempre!!

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Education

  • Master en Dirección Estratégica en Tecnologías de Información, Tecnología de la información
    Universidad Europea del Atlántico
    2016
    Master en Dirección Estratégica en Tecnologías de Información, Tecnología de la información
  • Computer science, Network and security
    Universidad Central de Venezuela
    2005
    Computer science, Network and security

Certifications

Skill set

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