The vulnerability in mayswind ezBookkeeping prior to version 2.0.0 involves the improper handling of Time-based One-Time Password (TOTP) codes. Specifically, the software does not invalidate TOTP passcodes after they have been used, permitting attackers to capture and replay these codes within the acceptance window. An attacker with stolen credentials can exploit this flaw to authenticate multiple times by reusing a captured TOTP code during the roughly 90-second validity period, effectively bypassing intended multi-factor authentication protections.

Attackers who have obtained valid user credentials and captured a TOTP code can bypass the intended one-time use restriction of the authentication code. This enables multiple unauthorized authentication attempts within the acceptance window without detection, increasing the risk of account compromise despite the presence of multi-factor authentication.

No official patch or remediation information is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should consider additional compensating controls such as monitoring for suspicious login activity or temporarily disabling TOTP-based authentication if feasible.