How should security teams reduce the risk of password reuse across systems?

Why This Matters for Security Teams

Password reuse is an identity propagation problem, not just a password hygiene problem. When the same secret unlocks user portals, admin consoles, scripts, and infrastructure, one compromise can become broad lateral movement. Security teams often discover the blast radius only after a token theft, phishing event, or exposed config file has already been used to pivot across systems. Current guidance in NIST Cybersecurity Framework 2.0 still points teams toward access control, asset visibility, and recovery discipline, but password reuse defeats all three when credentials are duplicated.

NHIMG research shows why this matters operationally: in The State of Non-Human Identity Security, Astrix Security & CSA report that only 1.5 out of 10 organisations are highly confident in securing NHIs. That confidence gap is often a symptom of unmanaged credential sprawl, where the same secret is reused in automation, service accounts, and vendor integrations. In practice, many security teams encounter the real risk only after a reused credential has already been used to access multiple systems rather than through intentional discovery.

How It Works in Practice

The practical response is to reduce credential overlap and make each login path uniquely attributable. Start by inventorying where passwords, API keys, and shared admin credentials are reused across applications, infrastructure, scripts, and third-party integrations. Then replace shared secrets with unique identities, ideally tied to role, workload, or device rather than a single reusable password. Where human access is required, use strong MFA and privileged access management; where automation is involved, use workload identity and short-lived credentials instead of static passwords.

For human accounts, the right pattern is usually unique identity plus least privilege plus revocation that can be verified. For machine and service access, teams should prefer ephemeral credentials, JIT provisioning, and central policy enforcement over long-lived passwords embedded in code or configuration. That aligns with the broader NHI guidance in Top 10 NHI Issues and with the emerging control patterns in OWASP NHI Top 10, especially where service credentials are overprivileged or never rotated.

• Map every reused credential to its systems, owners, and privilege level.
• Remove shared logins first from admin paths and production access.
• Issue unique credentials per user, per workload, or per integration.
• Enforce rotation and revocation on a defined schedule, not by exception.
• Monitor for duplicate secrets in vaults, repos, CI/CD pipelines, and config files.

Where possible, replace password-based trust with identity-based trust and policy checks at request time. These controls tend to break down when legacy applications only support a single shared local account because identity attribution and revocation become inseparable from the application itself.

Common Variations and Edge Cases

Tighter credential control often increases operational overhead, requiring organisations to balance simpler administration against lower blast radius. That tradeoff becomes most visible in legacy environments, shared administrative jump boxes, and vendor-managed systems where unique credentials are not easily supported. Best practice is evolving, but there is no universal standard for every exception path yet.

In those environments, teams should isolate the exception rather than normalise it: wrap the shared access behind PAM, monitor every session, and require compensating controls such as time-bound access, session recording, and immediate revocation after use. For service accounts, the safest option is usually to eliminate passwords entirely in favour of federated identity, certificate-based auth, or scoped tokens with short TTLs. The Ultimate Guide to NHIs — Why NHI Security Matters Now is useful context for why this shift matters: once a secret is reused across systems, compromise becomes multiplicative rather than isolated.

For organisations measuring progress, the key question is not whether passwords are strong, but whether any single credential can still unlock more than one meaningful system. That is the condition that turns routine credential theft into enterprise-wide exposure.

Related resources from NHI Mgmt Group

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• How should security teams make NHI best practices usable across the business?