Security Engineer - Email Security

About Us 

Zelis is modernizing the healthcare financial experience in the United States (U.S.) across payers, providers, and healthcare consumers. We serve more than 750 payers, including the top five national health plans, regional health plans, TPAs and millions of healthcare providers and consumers across our platform of solutions. Zelis sees across the system to identify, optimize, and solve problems holistically with technology built by healthcare experts – driving real, measurable results for clients.

At Zelis, AI is woven into the fabric of how we work. Every associate is expected - and empowered - to partner with AI to challenge the status quo, accelerate innovation, and amplify their impact. This is a place for builders with a growth mindset who act with agility, embrace change, and use modern technology to shape smarter solutions, exceptional experiences, and the future of our industry for our clients, customers, and our culture.

Why We Do What We Do 

In the U.S., consumers, payers, and providers face significant challenges throughout the healthcare financial journey. Zelis helps streamline the process by offering solutions that improve transparency, efficiency, and communication among all parties involved. By addressing the obstacles that patients face in accessing care, navigating the intricacies of insurance claims, and the logistical challenges healthcare providers encounter with processing payments, Zelis aims to create a more seamless and effective healthcare financial system.

Zelis India plays a crucial role in this mission by supporting various initiatives that enhance the healthcare financial experience. The local team contributes to the development and implementation of innovative solutions, ensuring that technology and processes are optimized for efficiency and effectiveness. Beyond operational expertise, Zelis India cultivates a collaborative work culture, leadership development, and global exposure, creating a dynamic environment for professional growth. With hybrid work flexibility, comprehensive healthcare benefits, financial wellness programs, and cultural celebrations, we foster a holistic workplace experience. Additionally, the team plays a vital role in maintaining high standards of service delivery and contributes to Zelis’ award-winning culture. 

Position Overview

Zelis is seeking a Security Engineer - Email Security to support and enhance the security, reliability, and protection of our enterprise email environment. This role will focus on identifying and preventing email-based threats, administering email security controls, troubleshooting mail-flow and security issues, and supporting Microsoft 365/Exchange Online environments. 

Proven experience designing and implementing enterprise-grade email security guardrails in regulated fintech or healthcare environments using technologies such as Microsoft Purview, Proofpoint, Microsoft Exchange Online, EasyDMARC, Abnormal Security, and adaptive AI-based threat protection, with a strong security-first mindset and expertise in phishing and BEC prevention, email authentication, data loss prevention, policy enforcement, monitoring, and incident response.

Security Engineer – Email Security 

Position Summary 

Zelis is seeking a Security Engineer - Email Security to support and enhance the security, reliability, and protection of our enterprise email environment. This role will focus on identifying and preventing email-based threats, administering email security controls, troubleshooting mail-flow and security issues, and supporting Microsoft 365/Exchange Online environments. 

The ideal candidate has hands-on experience with Microsoft Exchange, email security technologies, phishing investigations, mail-flow analysis, and security incident response. This individual will work closely with Security Operations, Messaging/Infrastructure, Identity, and other technology teams to protect the organization from phishing, business email compromise (BEC), malware, spoofing, and other email-based threats. 

Key Responsibilities 

• Perform detailed analysis of suspicious messages, including email headers, message routing, URLs, attachments, sender reputation, authentication results, and other indicators of compromise. 

• Administer and support email security controls within Exchange Online, Defender for O365, EasyDMARC, and Abnormal environments. 

• Troubleshoot email delivery, mail-flow, quarantine, filtering, and security-policy issues. 

• Review and analyze Exchange message traces and mail-flow logs to determine message disposition and identify security or delivery issues. 

• Configure and maintain mail-flow rules, anti-spam policies, anti-phishing protections, allow/block lists, quarantine policies, and related email security controls. 

• Support incident containment and remediation activities, including message removal, sender/domain blocking, URL blocking, mailbox remediation, and escalation of compromised accounts. 

• Assist with administration and tuning of Microsoft Defender for Office 365 or comparable secure email gateway/email security technologies. 

• Analyze and troubleshoot email authentication technologies including SPF, DKIM, and DMARC. 

• Identify false positives and false negatives and recommend improvements to email security policies and detection rules. 

• Document investigations, findings, remediation actions, and recurring email security issues. 

• Create and maintain operational procedures, troubleshooting guides, and knowledge-base documentation. 

• Collaborate with SOC, Incident Response, Identity and Access Management, Infrastructure, and Messaging teams during security investigations. 

• Assist with email security metrics, reporting, trend analysis, and continuous improvement initiatives. 

• Stay current on emerging phishing techniques, business email compromise tactics, attacker infrastructure, and email security best practices. 

Required Qualifications 

• 5+ years of proven experience designing and implementing enterprise-grade email security guardrails in regulated fintech or healthcare environments with a strong security-first mindset and expertise in phishing and BEC prevention, email authentication, data loss prevention, policy enforcement, monitoring, and incident response.  

• 3+ years of hands-on experience with Microsoft Exchange, Exchange Online, or Microsoft 365 messaging environments. 

• Working knowledge of Microsoft Exchange mail flow, connectors, transport/mail-flow rules, message tracking, and message tracing. 

• Experience investigating phishing, spam, malware, spoofing, and business email compromise incidents. 

• Strong understanding of email protocols and technologies, including SMTP, DNS, SPF, DKIM, and DMARC. 

• Experience analyzing email headers and determining message origin, routing, authentication results, and potential indicators of malicious activity. 

• Familiarity with Microsoft Defender for Office 365, Exchange Online Protection (EOP), or similar enterprise email security platforms. 

• Understanding common attacker techniques involving credential phishing, malicious attachments, malicious URLs, impersonation, and account compromise. 

• Strong analytical, troubleshooting, documentation, and communication skills. 

• Ability to independently investigate moderately complex incidents and appropriately escalate high-risk or advanced threats. 

Preferred Qualifications 

• Experience with Microsoft Defender for Office 365, including Safe Links, Safe Attachments, Threat Explorer, automated investigation and response, and related capabilities. 

• Experience using Microsoft Purview, Microsoft Sentinel, or the Microsoft Defender security ecosystem. 

• Experience with PowerShell for Exchange Online administration, investigation, or automation. 

• Familiarity with Entra ID/Azure AD authentication, Conditional Access, MFA, and identity-related investigations. 

• Experience investigating compromised Microsoft 365 accounts and malicious inbox or forwarding rules. 

• Knowledge of email security gateways or platforms such as Proofpoint, Mimecast, Cisco Secure Email, Abnormal Security, or similar technologies. 

• Familiarity with threat intelligence concepts, indicators of compromise (IOCs), and attacker tactics, techniques, and procedures (TTPs). 

• Relevant certifications such as Microsoft Security certifications, Security+, CySA+, GIAC, or equivalent industry certifications. 

Level II Expectations 

The Security Engineer - Email Security II is expected to operate with moderate independence and serve as an escalation point for routine and moderately complex email security issues. The engineer should be capable of conducting end-to-end phishing and email security investigations, troubleshooting Microsoft Exchange and Microsoft 365 email-security issues, recommending remediation actions, and recognizing when an incident requires escalation to senior security or incident response personnel. 

The engineer will also contribute to improving operational processes, detection capabilities, documentation, and automation while providing technical guidance to Junior Associates. 

Core Competencies 

• Email Security & Threat Analysis 

• Microsoft Exchange / Exchange Online 

• Microsoft 365 Security 

• Microsoft Defender for Office 365 

• Phishing & Business Email Compromise Investigation 

• Email Header & Mail-Flow Analysis 

• SPF, DKIM & DMARC 

• Security Operations 

• Troubleshooting & Root Cause Analysis 

• PowerShell / Security Automation 

• Technical Documentation 

• Cross-functional Collaboration 

 

Commitment to Diversity, Equity, Inclusion, and Belonging

At Zelis, we champion diversity, equity, inclusion, and belonging in all aspects of our operations. We embrace the power of diversity and create an environment where people can bring their authentic and best selves to work. We know that a sense of belonging is key not only to your success at Zelis, but also to your ability to bring your best each day.

Equal Employment Opportunity

Zelis is proud to be an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by federal, state or local laws.

Accessibility Support

We are dedicated to ensuring our application process is accessible to all candidates. If you are a qualified individual with a disability and require reasonable accommodation with any part of the application and/or interview process, please email [email protected].