Why does centralising passwords and TOTP secrets create additional security risk?

Centralising both factors increases risk because it can turn one repository into a single point of failure. If an attacker gains access to the vault, they may obtain the password and the time-based code needed for login, which weakens the protection multi-factor authentication is supposed to provide. The control objective is to preserve access convenience without collapsing independent layers of authentication.

Why Centralising Passwords and TOTP Secrets Changes the Security Model

Centralising both secrets can be convenient, but it also concentrates trust into one place. If the vault, browser profile, password manager, or sync layer is compromised, the attacker may inherit both the primary credential and the second factor needed to complete login. That turns a layered control into a tightly coupled bundle, where compromise is no longer blocked by factor independence. Current guidance suggests treating factor separation as a design property, not a storage preference.

For teams managing shared access, the main issue is not the existence of a vault itself but whether the vault has become the same asset that authenticates and authorises access everywhere else. When one repository can unlock many services, its compromise radius grows faster than most teams expect. Entro Security’s 2025 research notes that 62% of secrets are duplicated and stored in multiple locations, which is a reminder that hidden redundancy often expands exposure instead of improving resilience.

In practice, many security teams only discover the problem after a single vault or sync account becomes the easiest path to broad account takeover.

How the Risk Shows Up in Real Workflows

The security problem is architectural. Passwords and TOTP seeds are meant to be independent factors, so an attacker who steals one should still face a separate barrier. When both are centralised together, the second factor stops behaving like a separate challenge and becomes just another secret stored beside the first. That means the usual MFA protection depends on the vault remaining uncompromised, correctly segmented, and inaccessible to the same identity used for everyday sign-in.

This creates several practical failure modes. Endpoint malware can target the password manager or synced browser profile. Session hijacking or cloud account compromise can expose both stored credentials and enrolled TOTP seeds. Weak vault permissions, shared recovery channels, and export functions can also collapse the separation you thought you had. If the central store is backed up, replicated, or shared across devices, the blast radius may extend far beyond the original workstation.

• Separate where the factors are stored from where they are used.
• Limit vault access to the smallest set of identities and devices.
• Protect recovery paths as seriously as the primary vault.
• Prefer short-lived access and re-authentication for sensitive secret viewing.

For readers who want a deeper baseline on secret concentration and lifecycle weakness, the Guide to the Secret Sprawl Challenge is a useful companion, and the OWASP Non-Human Identity Top 10 frames the broader risk of over-centralised secret handling. These controls tend to break down when the same endpoint, sync account, or recovery workflow can reveal both factors without a separate trust check.

Common Exceptions, Trade-offs, and Control Boundaries

Tighter separation often increases user friction, so organisations have to balance convenience against recoverability and operational speed. That trade-off is real, especially in small teams that need fast access during incidents or on-call work. But convenience should not mean collapsing the independence of authentication factors; it should mean reducing unnecessary repetition while preserving a meaningful second barrier.

There are also edge cases where centralisation is less risky, but only under stronger compensating controls. For example, a vault that stores both password and TOTP seed may be less concerning if it is hardware-backed, strongly segmented, requires separate re-authentication for secret display, and is protected by device binding and monitored administrative access. Even then, the design still concentrates risk, so the question becomes whether the residual exposure is acceptable for the system being protected.

Teams should be especially cautious where the same person, device, or service account can unlock the vault and also access the downstream environment. That pattern quietly turns authentication into a single failure domain. When organisations scale, the issue is usually not one highly sensitive vault entry but many ordinary ones following the same pattern, which makes exposure cumulative rather than exceptional.

Practitioner Guidance

What to prioritise: Treat any location that stores both the password and the TOTP seed for the same account as a high-value authentication asset, not a convenience feature. Focus first on the accounts that can reach production, admin consoles, and recovery settings.

What to verify: Confirm that vault compromise does not automatically reveal both factors through export, sync, backup, browser autofill, or shared recovery flows. If it does, the design has effectively removed MFA separation.

Decision rule: If the same compromise path can recover both secrets, move the account to a stronger factor boundary rather than relying on monitoring to compensate after the fact.

Practitioner takeaway: The real risk is not central storage by itself; it is central storage that lets one compromise satisfy every step needed to authenticate.

Related resources from NHI Mgmt Group

• Why do collaboration tools create such a large secrets risk?
• What is secrets sprawl and why does it create security risk?
• Why do non-human identities create more audit risk than human accounts?
• Why do non-human identities create audit risk in modern environments?