A shared account is a single login used by multiple people instead of one named user. It is common for vendor portals, emergency access, service consoles, and low-friction team workflows, but it weakens accountability because actions cannot be easily tied to one person. Shared logins also make offboarding, password rotation, and privilege review harder, especially when the same credential is copied into chat, spreadsheets, or notes.
In cyber security, shared accounts matter because they blur the audit trail. Attackers often look for them since one stolen password can give access to systems used by an entire team, and defenders may struggle to see who changed settings, exported data, or approved access. Good practice is to replace shared logins with named accounts, role-based access, multifactor authentication, and centralized logging. Where sharing is unavoidable, organizations should use a password manager or privileged access system that records use, limits exposure, and supports regular rotation.