Full-Time

Senior Specialist

IT Security Operations, Open

Posted on 12/6/2025

Marsh

Marsh

10,001+ employees

Global insurance brokerage and risk advisory

No salary listed

London, UK

Hybrid

Three days per week on-site in-office requirement.

Category
IT & Security (1)
Required Skills
TCP/IP
Wireshark
Linux/Unix
Requirements
  • 5+ years of network security experience within large-scale operations.
  • One or more of the following:Cisco ASA, FirePower, Palo Alto, BlueCoat Proxy, Zscaler, F5 ASM FireEye
  • Expertise knowledge of TCP/IP and related protocols and with collecting and evaluating HTTPS & TCP/IP dumps using Wireshark, HTTPWatch, tcpdump, Fiddler, and similar tools.
  • Strong analytical, problem-solving, and root cause analysis skills relating to security operations technologies.
  • Excellent verbal, written and collaborative interpersonal communication skills.
  • Working knowledge of Unix/Linux CLI.
Responsibilities
  • Tier II-IV troubleshooting incident
  • Change and configuration management
  • Policy optimization
  • Infrastructure management
  • Capacity management
  • Patch and OS management
  • Event monitoring and alerting
  • Vulnerability management
  • Cybersecurity Incident Response
  • Security Projects
  • Risk Reduction through policy optimization and audit
Desired Qualifications
  • Administration of Blue Coat Proxy SG 250-430 certification.
  • Blue Coat Proxy Administrator or Professional (BCCPA or BCCPP) certification.
  • PaloAlto Networks PCNSE v9 certification.
  • FireEye HX & NX experience and certifications.
  • F5 Application Security Manager (ASM) expertise & Exam 303-BIG-IP ASM Specialist.
  • Cisco ASA & Firepower with CCNA CyberOps, CCNA Security, and/or CCNP Security certifications.
  • Experience operating within AWS and Azure environments.
  • SANS/GIAC certifications

Marsh is a diversified professional services firm that helps clients manage risk, secure insurance, and design risk-transfer programs. Its core work combines risk advisory with insurance brokerage, acting as a buyer of coverage and placing policies across multiple underwriters. It includes Mercer (HR consulting), Guy Carpenter (reinsurance brokerage), and Oliver Wyman (management consulting) under a holding structure. Its goal is to lower clients' financial risk and total cost of risk by combining risk transfer with advisory and consulting services across insurance, reinsurance, HR, and business strategy.

Company Size

10,001+

Company Stage

Seed

Total Funding

$110K

Headquarters

New York City, New York

Founded

1871

Simplify Jobs

Simplify's Take

What believers are saying

  • Mercer consulting revenue grew 11% in Q1 2026, outpacing traditional brokerage and driving higher margins.
  • EMEA division surged 14.1% year-over-year in Q1 2026, signaling strong European and emerging market expansion.
  • Niche insurance products like Port Blockage Insurance and Micassure capture underserved segments as commoditization pressures traditional lines.

What critics are saying

  • Aon's $13B Willis Towers Watson acquisition enables aggressive pricing that erodes Marsh's 30% global brokerage share.
  • Guy Carpenter's 2% organic growth in Q1 2026 trails Arthur J. Gallagher's 15% YoY, signaling reinsurance market share loss.
  • Sentrisk AI platform faces class-action lawsuits alleging misuse of client supply chain data for competitive intelligence.

What makes Marsh unique

  • Sentrisk AI platform maps supply chains with geospatial satellite imaging, uniquely addressing geopolitical and climate risks.
  • Holding company structure enables separately managed businesses: Marsh, Mercer, Guy Carpenter, Oliver Wyman.
  • Broker-as-advisor model since 1905 spreads client risk across multiple underwriters, not single insurers.

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Benefits

Health Insurance

Dental Insurance

Vision Insurance

Life Insurance

Disability Insurance

Paid Vacation

Paid Sick Leave

Hybrid Work Options

401(k) Retirement Plan

401(k) Company Match

Employee Stock Purchase Plan

Professional Development Budget

Tuition Reimbursement

Mental Health Support

Paid Holidays

Company News

Smartbroker Holding AG
Jul 28th, 2025
Mitsubishi Electric to Transfer Shares of Insurance Subsidiary to Marsh Japan

28.07.2025 - Mitsubishi Electric Corporation (TOKYO: 6503) announced today that it has concluded a share transfer agreement under which it will transfer shares of its Tokyo-based subsidiary Mitsubishi Electric Insurance Service Co., Ltd. to Marsh Japan, Inc. on ...

Coverager
Aug 28th, 2024
Marsh Launches Port Blockage Insurance

Marsh <i class="fa fa-info-circle company-popover" data-content="h3Marsh/h3. div. table

Business Wire
May 16th, 2024
Marsh Mclennan Stockholders Re-Elect Board Of Directors During 2024 Meeting

NEW YORK--(BUSINESS WIRE)--Marsh McLennan (NYSE: MMC), the world’s leading professional services firm in the areas of risk, strategy, and people, today announced the results of its 2024 Annual Meeting of Stockholders. Stockholders elected the entire slate of 2024 director nominees for a one-year term expiring at next year’s annual meeting. The 11 directors are: Anthony K. Anderson, John Q. Doyle, Oscar Fanjul, H. Edward Hanway, Judith Hartmann, Deborah C

Coverager
May 9th, 2024
Marsh Introduces Micassure

Marsh <i class="fa fa-info-circle company-popover" data-content="h3Marsh/h3. div. table

Coverager
May 2nd, 2024
Marsh Launches Sentrisk

Marsh <i class="fa fa-info-circle company-popover" data-content="h3Marsh/h3. div. table

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