Token persistence is continued access that remains active after a password change because an authentication token, session cookie, refresh token, or device credential is still valid. Many cloud and web systems use tokens so users do not have to re-enter passwords on every request.
It matters because password resets do not automatically end every session. If an attacker steals a valid token through phishing, malware, browser session theft, or consent abuse, they may keep accessing email, files, or cloud apps until the token expires or is revoked. Defenders counter this by revoking sessions, invalidating refresh tokens, reviewing sign-ins, and enforcing conditional access and multifactor authentication. Monitoring unusual token use is important because persistent tokens can make intrusions look like normal user activity.