Senior Security Engineer Consultant

Mission Overview:

Keystone Solutions is seeking an experienced Security Engineer for a consultancy mission at a client site. The consultant will play a crucial role in enhancing the security posture of information systems within the water sector in Wallonia, focusing on operational security and compliance with NIS2 regulations.

Key Responsibilities:

• Participate in operational security (SecOps) for both internal systems and clients.
• Administer, configure, and optimize Security Centers (SIEM, EDR, vulnerabilities).
• Manage SOC alerts: qualification, analysis, escalations, and coordination with technical teams.
• Engage in incident response activities: containment, analysis, remediation, and reporting.
• Establish and adjust detection rules, dashboards, alerts, and playbooks.
• Configure and secure client technical environments: servers, networks, cloud, firewalls.
• Maintain and adjust security tools: EDR, SIEM, IDS/IPS, anti-malware solutions.
• Develop security-related projects such as unified vulnerability management.
• Apply hardening benchmarks (CIS, ANSSI, NIST).
• Conduct technical security reviews of projects and propose remediation plans.
• Document architectures, configurations, and security parameters.
• Contribute to internal and client technical risk analyses.
• Participate in drafting and improving policies, procedures, and processes.
• Prepare and support audits (internal, client, NIS2).
• Produce posture reports, KPIs, and security dashboards.
• Collaborate with systems, network, development, and support teams.
• Provide technical security advice in internal and client projects.
• Participate in security awareness initiatives for teams as needed.

Required Skills:

• Soft Skills: Attention to detail, analytical mindset, clear communication, autonomy, initiative, collaborative spirit, and service orientation.
• Technical Skills: Strong knowledge of Windows Server / Linux environments, networking concepts (firewalls, VLAN, VPN, routing, segmentation), experience with EDR/XDR, SIEM, and SOC tools, system hardening practices, and familiarity with Azure / Entra ID / Microsoft 365.
• Language: Proficient in French and technical English.

Experience:

• 5+ years of experience in a security engineer role, SecOps, or security-focused system/network engineering.
• Proven experience in administering security tools (EDR, SIEM, monitoring).
• Experience in incident response or SOC monitoring is preferred.
• Experience in MSP, MSSP, or multi-client environments is highly valued.
• Strong knowledge of NIS2 directive, ISO 27001, or equivalent frameworks.
• Technical or security certifications are appreciated (MS-500/SC-200, CySA+, CEH, etc.).

If you are ready to tackle technical and strategic challenges in a dynamic consultancy environment, apply today at Keystone Solutions Career Portal .

Duration: 01/07/2026 - 30/06/2027 12 months • (full time)

Skills required:

• Compétences « soft skills »
• Rigueur et sens du détail, indispensable pour les environnements critiques.
• Esprit analytique, capacité à diagnostiquer et résoudre des incidents complexes.
• Clarté de communication, aussi bien avec des profils techniques que non techniques.
• Autonomie et initiative, capacité à prioriser dans un contexte multi-clients.
• Esprit collaboratif, travail en équipe avec le CISO, l’ISM et les équipes techniques.
• Sens du service, essentiel pour les activités MSP et la relation client.
• Compétences techniques (niveau fonctionnel/encadrement)
• Très bonnes connaissances des environnements Windows Server / Linux.
• Maîtrise des concepts réseau : firewalls, VLAN, VPN, routage, segmentation.
• Expérience en solutions EDR/XDR, SIEM et outils SOC.
• Pratique du durcissement système et des benchmarks (CIS, NIST, ANSSI).
• Connaissances en Azure / Entra ID / Microsoft 365 / Microsoft Security Center appréciées.
• Compréhension des vulnérabilités, CVE, scoring, remédiation.
• Bonne maîtrise de la documentation technique.
• Une expérience sur environnements multi-clients / MSP est un atout majeur.
• Langue : Maitrise parfaite du français et de l’anglais technique
• Expérience
• 5 à 7 ans d’expérience dans un rôle d’ingénieur sécurité, SecOps ou ingénieur système/réseau orienté sécurité.
• Expérience confirmée dans l’administration d’outils sécurité (EDR, SIEM, monitoring).
• Expérience en réponse aux incidents ou suivi SOC souhaitée.
• Expérience MSP, MSSP ou multi-clients fortement appréciée.
• Connaissance avérée de la directive NIS2, ISO 27001 ou cadres équivalents
• Certifications techniques ou sécurité appréciées (MS-500/SC-200, CySA+, CEH, etc.).
• View more
• Job specifications
• Ingénieur Sécurité_12062026.docx

Language requirements:

English
Level Professional working proficiency
French
Level Native or bilingual proficiency