How do modern identity attacks target healthcare?
Healthcare identity attacks are cyberattacks that exploit compromised user credentials, session cookies, API tokens, or non-human AI agents to gain unauthorized access to Electronic Health Records (EHRs), claims systems, and medical networks. Unlike traditional perimeter breaches, modern healthcare identity attacks leverage Adversary-in-the-Middle (AitM) phishing, session hijacking, credential stuffing, and prompt injection against non-human identities to bypass traditional multi-factor authentication (MFA).
What is healthcare identity security?
Healthcare identity security is the practice of protecting the credentials, sessions, and access rights of clinicians, staff, patients, and the growing number of AI agents that touch electronic health records (EHRs), claims systems, and telehealth platforms. As health systems, payers, and life sciences companies race to modernize care delivery, attackers have found that the fastest way in isn't through a hospital firewall—it's through a stolen login.
Static perimeters don't exist in a cloud-first, SaaS-saturated environment. Identity is the common thread connecting clinicians, patients, administrative staff, connected devices, and the automated agents now embedded in scheduling, billing, and clinical workflows. Attackers have pivoted accordingly: instead of breaching hospital networks directly, they simply log in.
The scale of the threat
In 2025, healthcare organizations reported 772 large data breaches to the US Department of Health and Human Services Office for Civil Rights, exposing roughly 138.5 million patient records—and hacking or IT incidents accounted for more than 80% of them, according to HIPAA Journal. At the same time, generative AI has lowered the cost of running convincing, personalized phishing campaigns, and autonomous AI agents operating as non-human identities inside clinical and administrative systems have introduced an entirely new attack surface.
Here's how modern identity attacks unfold in healthcare across four distinct phases, and what a healthcare-grade identity defense actually requires:
- Reconnaissance and infiltration: Exploiting stolen credentials and credential stuffing to gain initial access
- Exploiting AI and machine access: Targeting service tokens, API keys, and autonomous AI agents
- Hijacking active sessions: Stealing live session cookies to bypass multi-factor
- Insider threats: Navigating accidental data exposure, compromised devices, and malicious abuse of legitimate access
How do threat actors execute identity reconnaissance and infiltration in healthcare?
Legacy attacks on healthcare relied on generic phishing emails and brute-force login attempts. Today, attackers use AI to run hyper-targeted, automated campaigns against the people who hold the keys to patient data: front-desk and scheduling staff, revenue-cycle and billing teams, and clinicians who move quickly between patients and systems.
AI-generated lures
Where traditional spam filters caught poor grammar or generic subject lines, threat actors now use AI agents to scrape staff directories, EHR vendor conference attendee lists, and public professional profiles to craft convincing, role-specific lures—a "portal access" email that looks like it came from the health system's own IT help desk, or a fake prior-authorization request that mimics a payer's format.
Adversary-in-the-middle (AitM) proxies
Attackers increasingly deploy adversary-in-the-middle (AitM) proxies to capture both a clinician's primary credentials and their real-time MFA token in a single interaction, handing them a live session rather than just a password.
Credential stuffing through residential proxies
Brute-force and credential-stuffing attacks have scaled the same way. Attackers aggregate combolists harvested from infostealer malware and route login attempts through rotating residential proxies, testing reused passwords against patient portals, scheduling systems, and payer login pages without tripping rate limits. Because so many clinicians and staff reuse credentials across personal and work accounts, a single compromised password from an unrelated breach can become the entry point to a hospital's EHR.
According to the Verizon 2025 Data Breach Investigations Report, compromised credentials remain the initial access vector in 22% of confirmed data breaches across the industry. Healthcare-specific MFA adoption tends to lag other regulated industries: Okta's 2025 Secure Sign-in Trends Report found that even as overall workforce MFA adoption reached 70% across industries, 30% of enterprise users still have no MFA protection at all, and basic factors remain highly susceptible to MFA bombing and AitM interception.
Download: 5 Identity Attacks that Exploit Your Broken Authentication
How do attackers exploit AI and non-human identities in EHRs?
The traditional threat model assumed a human was behind every credential. In healthcare, that assumption is now dangerously outdated. AI scribes that document patient encounters, clinical decision-support agents, and automated prior-authorization and claims-processing bots are proliferating fast—and most are provisioned with broad, standing access to EHRs, claims databases, and scheduling systems so they can act without waiting on a human in the loop.
That convenience is exactly what attackers are learning to exploit. Rather than targeting a nurse's or claims adjuster's password, attackers go after the API keys, service tokens, and OAuth grants issued to these agents. If an attacker hijacks an underlying service token or manipulates an agent through prompt injection, the agent executes malicious actions (such as pulling patient records, altering claims data, or rescheduling and canceling appointments at scale) with the full authorization of its system role, and at machine speed. What would take a human attacker days to accomplish manually, a compromised agent can do in seconds.
The governance gap
Okta's Businesses at Work 2026 report found that while 58% of executives cite AI governance as their top security concern, fewer than one-third secure AI agents with the same rigor applied to human employees—a gap that's especially dangerous in an industry where a single compromised claims-processing or scheduling agent can touch millions of patient records in seconds.
How do attackers hijack active clinical sessions and bypass MFA?
As the adoption of stronger MFA grows, attackers have adapted by targeting post-authentication sessions rather than the login screen.
Session cookie theft
Using malware to steal active session cookies from clinician workstations, shared nursing-station devices, or remote and telehealth endpoints, attackers can replay a live session and bypass MFA entirely—no password or security key required. A hijacked telehealth session or an active patient-portal session grants an attacker the same access as a legitimate clinician or patient, without ever triggering a login alert.
Lateral movement across vendors and networks
Once inside, attackers exploit exactly the kind of fragmented, disconnected environment healthcare IT stacks are known for. A health system might enforce a strict sign-on policy at the EHR or core identity provider level, but once a session is established in one connected application, attackers can move laterally through referral networks, lab and imaging integrations, and third-party billing or scheduling vendors.
Third-party risk metrics and assessment gap
That last category has become the fastest-growing part of the healthcare attack surface. Ransomware attacks against healthcare businesses—billing vendors, health tech platforms, and service partners, as distinct from hospitals and clinics themselves—rose 51% in 2025 even as attacks on direct-care providers fell 8%, according to Comparitech data reported by Industrial Cyber. Two of 2025's largest healthcare breaches—Conduent Business Services (62.2 million individuals) and Episource (6.7 million individuals)—both originated at a business associate rather than the health system whose patients were exposed. Yet only 4% of healthcare organizations report high confidence in their vendor risk assessments, and nearly 30% report no confidence at all, per Cybersecurity Dive. Attackers know that a single compromised billing partner or scheduling vendor can be the doorway to dozens of downstream health systems and payers at once.
What forms do insider identity threats take in healthcare systems?
Not every healthcare identity attack originates outside the organization. Insider risk in healthcare spans three distinct categories:
Negligent insiders
Many identity attacks start with negligent insiders—clinicians and staff who cause incidents through unintentional mistakes, like pasting patient information into an ungoverned consumer AI tool for a quick summary, ignoring a security patch on a clinical workstation, or misconfiguring sharing permissions on a folder full of case files.
Compromised insiders
A compromised insider is a legitimate staff member whose device has been quietly infected with infostealer malware, turning a trusted EHR login into an unwitting proxy for an outside attacker.
Malicious insiders
A malicious insider is an employee or contractor who deliberately abuses standing access—browsing patient records without a clinical reason, exfiltrating research data, or selling access to patient information outright. This pattern, often described as medical identity theft, remains one of healthcare's most persistent and hardest-to-detect risks precisely because the access being abused is legitimate.
Life sciences organizations face a parallel version of this risk: a compromised or careless insider with access to clinical trial systems can just as easily corrupt trial data integrity as expose patient records, with regulatory consequences that extend well beyond a single breach notification. Without continuous risk scoring and fine grained access governance, standard security tools can't distinguish between a clinician doing their job and an insider abusing legitimate access.
Key requirements for a modern healthcare identity defense framework
To counter AI-velocity identity attacks, healthcare security architectures have to evolve past a single perimeter check at login. A modern healthcare identity defense strategy rests on four core principles:
- Phishing-resistant authentication by default: Move clinicians, staff, and administrators beyond easily hijacked methods like SMS codes or basic push notifications. Passwordless authentication verifies both the user's device and the exact website domain before granting access—closing off AitM phishing without adding friction to clinical workflows.
- Extending governance to non-human and AI identities: Apply the same rigor to AI scribes, clinical agents, and claims-processing bots that you apply to human staff: least-privilege access scoped to a specific task, short-lived credentials instead of standing permissions, and human approval gates for high-risk actions like bulk record access or claims changes.
- Continuous session monitoring and risk signal sharing: Evaluate risk before, during, and after authentication—for every session, not just the login event. This allows for automatically ending a session or prompting re-verification when a sudden location change, an impossible travel pattern, or a malware signal appears, whether the session belongs to a clinician, a patient, or an AI agent.
- Unified access management, identity governance, and privileged access: Eliminate the blind spots created by managing general access, EHR and claims entitlements, and administrative rights in separate systems. Replacing standing administrative access with temporary, as-needed elevation means that a single stolen credential—from a clinician, vendor, or agent—can't become a system-wide compromise.
Transform identity into your strongest defense
Protecting sensitive patient data and preventing identity breaches requires a unified security foundation. From streamlining clinician access to safeguarding protected health information, identity is at the core of modern healthcare security.
Ready to secure every identity across your care ecosystem without impacting clinical workflows? Download the Why Okta for Healthcare whitepaper to explore how Okta helps healthcare organizations strengthen identity security, simplify access, and maintain HIPAA compliance.
These materials are intended for general informational purposes only and are not intended to be legal, privacy, security, compliance, or business advice. © 2026 Okta, Inc. and/or its affiliates.
