How should organisations reduce account takeover risk without relying on SMS 2FA?

Move high-risk accounts to phishing-resistant factors such as security keys or authenticator apps, then harden recovery and support flows so they are not easier to abuse than login. The best programmes also reduce standing trust by reviewing enrolment, device change, and re-binding as privileged identity events.

Why This Matters for Security Teams

SMS 2FA is better than passwords alone, but it is not a durable defence against account takeover. SIM swap attacks, number recycling, social engineering of telcos, and session theft can bypass a phone number that many teams still treat as a trust anchor. Current guidance from the NIST Cybersecurity Framework 2.0 and the Top 10 NHI Issues points in the same direction: reduce reliance on shared, reusable, weakly bound credentials and move toward stronger identity assurance.

The practical problem is that attackers rarely need to beat the login form if they can abuse recovery, device re-binding, or support processes. Those paths often have weaker checks than the primary sign-in flow, especially for high-value users, admins, and customer support queues. NHI Management Group research shows why standing trust is dangerous in adjacent identity systems as well: Ultimate Guide to NHIs — Key Challenges and Risks notes that 71% of NHIs are not rotated within recommended time frames, reinforcing how persistent credentials create avoidable exposure. In practice, many teams discover account takeover only after a recovery path or support workflow has already been abused.

How It Works in Practice

The safest pattern is to replace SMS with phishing-resistant factors and then harden the entire account lifecycle around that stronger assurance. Security keys and platform authenticator apps are the usual starting point, but the real control is not the factor alone. It is the binding between the user, the device, and the recovery process. Where possible, organisations should require step-up verification for device changes, new sessions, password resets, and changes to contact information.

For high-risk accounts, treat enrolment and re-binding as privileged identity events. That means logging them, reviewing them, and applying stricter policy than ordinary sign-in. Support staff should not be able to override identity checks casually, and recovery should not be easier than logging in. Many organisations also add device posture or session risk signals, but current guidance suggests those signals should augment rather than replace phishing-resistant authentication.

• Prefer FIDO2 security keys or passkeys over SMS codes for primary and backup authentication.
• Use short-lived sessions and re-authentication for sensitive actions, not just for login.
• Require stronger verification before changing MFA factors, email addresses, or phone numbers.
• Separate helpdesk privileges so recovery actions cannot be approved by a single low-trust operator.
• Alert on unusual enrolment, repeated recovery attempts, and rapid factor re-binding.

These controls map cleanly to the intent of Ultimate Guide to NHIs — Why NHI Security Matters Now, which frames identity trust as something to minimise and continually verify, not assume. They also align with the identity assurance and access governance themes in NIST Cybersecurity Framework 2.0. These controls tend to break down in large service desks or outsourced support environments because attackers target the weakest human approval path rather than the strongest technical factor.

Common Variations and Edge Cases

Tighter authentication and recovery controls often increase user friction and support cost, so organisations have to balance reduced takeover risk against operational overhead. That tradeoff is real, especially for consumer services, workforce portals, and high-volume call centres where password resets and device changes happen frequently.

There is no universal standard for every account type yet, but current guidance suggests segmenting by risk. Admin accounts, finance users, executives, and support operators should receive the strongest phishing-resistant factors and the most restrictive recovery paths. Lower-risk populations may need different rollout sequencing, stronger fallback verification, or temporary dual controls during migration away from SMS.

Some environments also need exceptions for legacy devices, shared workstations, or users who cannot reliably use hardware keys. In those cases, security teams should avoid silently falling back to SMS as the default rescue path. Instead, they should use supervised recovery, time-bound enrolment windows, and additional verification evidence. The key mistake is allowing the exception to become the standard. In practice, attackers exploit whichever identity path is easiest to socially engineer, not whichever one was designed to be most secure.

Related resources from NHI Mgmt Group

• How should IAM teams reduce account takeover risk without relying on passwords?
• How can organisations reduce account takeover risk without hurting user experience?
• How should healthcare organisations reduce identity risk without slowing clinical care?
• How should government teams reduce resident account takeover without adding too much login friction?