A host header injection vulnerability exists in gugoan's Economizzer v.0.9-beta1 and commit 3730880 (April 2023). By sending a specially crafted host header in the reset password request, it is possible to send password reset links to users which, once clicked, lead to an attacker-controlled server and thus leak the password reset token. This allows an attacker to reset other users' passwords.

A remote code execution (RCE) vulnerability via an insecure file upload exists in gugoan's Economizzer v.0.9-beta1 and commit 3730880 (April 2023). A malicious attacker can upload a PHP web shell as an attachment when adding a new cash book entry. Afterwards, the attacker may visit the web shell and execute arbitrary commands.

The commit 3730880 (April 2023) and v.0.9-beta1 of gugoan Economizzer is vulnerable to Clickjacking. Clickjacking, also known as a "UI redress attack", is when an attacker uses multiple transparent or opaque layers to trick a user into clicking on a button or link on another page when they were intending to click on the top-level page. Thus, the attacker is "hijacking" clicks meant for their page and routing them to another page, most likely owned by another application, domain, or both.

An Insecure Direct Object Reference (IDOR) vulnerability in gugoan Economizzer commit 3730880 (April 2023) and v.0.9-beta1 allows any unauthenticated attacker to access cash book entry attachments of any other user, if they know the Id of the attachment.

The commit 3730880 (April 2023) and v.0.9-beta1 of gugoan Economizzer has a user enumeration vulnerability in the login and forgot password functionalities. The app reacts differently when a user or email address is valid, and when it's not. This may allow an attacker to determine whether a user or email address is valid, or brute force valid usernames and email addresses.

A SQL injection vulnerability exists in gugoan Economizzer commit 3730880 (April 2023) and v.0.9-beta1. The cash book has a feature to list accomplishments by category, and the 'category_id' parameter is vulnerable to SQL Injection.