IT Cyber Security Specialist

Mission Overview:

Keystone Solutions is seeking an IT Cyber Security Specialist for a consultancy mission at a client site. The primary objective of this role is to enhance the operational security team responsible for protecting, detecting, and responding to cybersecurity incidents.

The consultant will integrate into the team as a SecOps engineer specializing in network and infrastructure security, contributing to the security operations while being available for on-call duties 24/7 in rotation with other team members.

Key Responsibilities:

• Manage daily security tools and incidents.
• Maintain and optimize security tools (excluding exploitation).
• Collaborate with the Security Operations Center (SOC) and other teams to enhance overall security.
• Participate in projects related to operational security.
• Respond on-call or on standby based on incident criticality.
• Handle security incidents (analysis, escalation, resolution) including documentation.
• Coordinate different teams for incident resolution or security improvement.
• Analyze network flows and correlate with alerts.
• Contribute to securing network architectures, configuration relevance, and exception management (impact and risk analysis).
• Participate in tuning protection and detection rules, especially on network security tools (WAF, IDS/IPS, NDR, Proxy, etc.).
• Establish exception management (impact and risk analysis).
• Provide transversal support on security tools.
• Conduct post-mortem analysis of incidents: technical retrospectives, recommendations, and follow-up on action plans with the ITSM team.
• Process alerts (SIEM, WAF, etc.) from the SOC and/or security tools.
• Conduct security monitoring and threat intelligence: tracking CVEs, IOCs, MITRE ATT&CK tactics.
• Participate in the development or continuous improvement of SecOps processes, procedures, and guides.
• Support IT projects related to operational security: security reviews, providing technical-functional advice, and active participation in project teams.
• Utilize ITSM tools (Jira Service Management, etc.).
• Perform any other activities related to operational security based on service needs and priorities.

Working Conditions:

This mission will be executed within the security division of the client under the supervision of the operational security manager. The consultant will provide regular full-time services (40 hours/week) and will ensure availability for on-call duties 24/7, with a commitment to respond to certain alerts within a maximum of 30 minutes.

The SOC and the client may call the consultant on duty to handle priority 1 or 2 incident analysis, take response actions, and coordinate teams until the incident is resolved. Integration into existing processes (incident management, change management, SOC, etc.) is essential.

Expected Deliverables:

• Activity and incident reports, progress reports on post-incident recommendations.
• NIS2: initial notification, preliminary report, and final report.
• Change log of rules (who, what, why).
• Optimized configurations of security tools.
• Technical documentation, processes, and procedures.
• Improvement recommendations and advice.
• Cyber dashboard, operational, tactical, and strategic reporting.
• Follow-up on security KPIs.

Expected Behavioral Competencies:

• Clear communication.
• Rigorous change management.
• Emergency management.
• Incident prioritization.
• Adaptability and learning capability.
• Technical curiosity.
• Autonomy.
• Team collaboration.
• Assertiveness and ability to challenge.

Evaluation Method:

The evaluation will include an interview where questions and/or situational assessments related to the mission description will be utilized.

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

Duration: 01/12/2026 - 14/06/2027 7 months • (full time)

Skills required:

• Gestion d’incident de sécurité (incident responder et/ou incident manager)
• (mandatory) - Level: T2 - Confirmed - Most recent: This year
• Gestion d’un IPS/IDS ou NDR
• (mandatory) - Level: T2 - Confirmed - Most recent: This year
• Gestion de la sécurité sur Firewall
• (mandatory) - Level: T2 - Confirmed - Most recent: Any time
• Sécurisation des DNS
• (mandatory) - Level: T1 - Junior - Most recent: Any time
• Sécurisation des proxy
• (mandatory) - Level: T1 - Junior - Most recent: Any time
• SOC (SIEM/XDR)
• (mandatory) - Level: T1 - Junior - Most recent: Any time
• WAF
• (mandatory) - Level: T1 - Junior - Most recent: Any time

Language requirements:

French
(mandatory)
Level Proficiency (C2)