Security teams should replace shared credentials with individually attributable access, centralized approval, and automation for granting and revoking permissions. Shared logins and shared SSH keys obscure accountability and make it difficult to verify who accessed sensitive systems. A modern access model should also align permissions to roles, so infrastructure can scale without relying on manual exceptions or prolonged standing access.
Why shared logins and shared keys create disproportionate access risk
Shared credentials make infrastructure access harder to trust because they collapse multiple people, shifts, and use cases into one identity path. That weakens attribution, complicates incident review, and makes it difficult to prove whether access was appropriate. The practical problem is not just convenience, it is that shared access removes the evidence teams need to separate legitimate work from misuse.
They also increase blast radius. If one shared login or key is exposed, every system or workflow that trusts it can be affected until the credential is found, rotated, and reissued. That is why shared access tends to linger as a hidden dependency: it may keep operations moving, but it also turns one secret into a reusable path into sensitive infrastructure.
Teams that are formalising non-human and shared access patterns often start with a central reference for governance and lifecycle concerns, such as Ultimate Guide to NHIs, because it frames why visibility, rotation, and offboarding matter together rather than as separate chores.
How to reduce risk without breaking operations
The best reduction strategy is to move from shared access to individually attributable access, then add approval and automation around that model. In practice, that means separating human access from shared operational needs, assigning permissions through roles or groups, and ensuring each grant can be reviewed, time-bounded, and revoked without relying on tribal knowledge.
Where shared logins cannot be eliminated immediately, teams should narrow them aggressively. Limit where the credential works, reduce standing access, rotate it on a fixed schedule, and require explicit ownership for every shared secret. A shared key that is still broadly usable across environments or teams is usually a sign that access design has not caught up with operational reality.
That is also where standards and playbooks become useful. The OWASP NHI guidance on secret sprawl, credential rotation, and overprivilege aligns closely with the controls teams need here, and CIS Controls v8 reinforces account management, access control, and audit logging as practical safeguards.
For organisations moving toward stronger access boundaries, NIST SP 800-207 Zero Trust Architecture is a useful reference point because it supports the shift away from implicit trust in a credential alone.
What good looks like in steady state
Good control is visible, attributable, and revocable. Every person who can administer infrastructure should have an identity that is distinct from any shared operational account, and every shared credential that remains should have a clear business owner, a documented purpose, and a defined retirement date. When that is in place, review becomes possible because teams can tell who used what, when, and why.
Good practice also means that permission changes are routine rather than exceptional. New access should flow through an approval path, not an ad hoc message, and revocation should be equally standardised. If the team cannot answer how fast a credential can be removed after someone changes role, leaves, or no longer needs access, the risk is still being carried by process rather than control.
For shared login and key risk, the most useful evidence is not intent, it is operational traceability. Teams should be able to show ownership, recent rotation, last use, and the systems a credential can reach. Without that evidence, the environment may appear manageable while still relying on access paths that are too broad, too old, or too hard to unwind.
Practitioner Guidance: If you cannot eliminate shared access immediately, treat it as a transitional control problem, not a permanent operating model. Prioritise the credentials with the broadest reach and the weakest auditability first, then use role design and automation to remove the need for manual exceptions over time.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 and MITRE ATT&CK address the attack and risk surface, while CIS Controls v8, NIST CSF 2.0, NIST SP 800-63 and NIST Zero Trust (SP 800-207) set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | Secret sprawl, credential rotation, overprivilege, third-party risk | Shared keys and logins are classic NHI governance risks. |
| Recommendation — Reduce shared-access exposure by rotating credentials, shrinking privilege, and removing broad third-party trust. | ||
| CIS Controls v8 | 5 — Account Management | Shared logins require stronger account ownership and lifecycle control. |
| 6 — Access Control Management | Access should be approved, limited, and revoked through formal control processes. | |
| 8 — Audit Log Management | Attribution is difficult without reliable logging of who used shared access. | |
| Recommendation — Assign unique accounts, review ownership, and disable shared access paths when they are no longer needed. Enforce least privilege and revoke access promptly when roles or tasks change. Log credential use centrally so shared-access activity can still be reviewed and investigated. | ||
| NIST CSF 2.0 | PR.AC — Identity Management, Authentication, and Access Control | The subject is fundamentally about reducing access risk through stronger identity and access control. |
| Recommendation — Apply identity and access controls that replace shared credentials with attributable, least-privilege access. | ||
| NIST SP 800-63 | AAL — Authenticator Assurance Level | Stronger authenticators reduce reliance on weak shared login practices. |
| Recommendation — Use higher-assurance authenticators for privileged infrastructure access and avoid shared secrets where possible. | ||
| NIST Zero Trust (SP 800-207) | 4 — Policy Engine, Policy Administrator, Policy Enforcement Point | Zero Trust reduces implicit trust in a credential alone and supports tighter access decisions. |
| Recommendation — Enforce access decisions centrally instead of trusting a shared credential to confer broad reach. | ||
Related resources from NHI Mgmt Group
- How should healthcare security teams reduce access risk in legacy enterprise systems with shared logins and manual approvals?
- How should security teams reduce ransomware risk in factory environments that still depend on Windows systems and shared operational access?
- How should security teams govern API keys used for generative AI access?
- How should security teams reduce cloud identity risk when credentials are stored in shared infrastructure?
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on September 20, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
