Package Instance

Firefly III allows webhooks HTML Injection.
Firefly III (aka firefly-iii) before 6.1.1 allows webhooks HTML Injection.

Firefly III has a MFA bypass in oauth flow
A MFA bypass in the Firefly III OAuth flow may allow malicious users to bypass the MFA-check. This allows malicious users to use password spraying to gain access to your Firefly III data using passwords stolen from other sources. As OAuth applications are easily enumerable using an incrementing id, an attacker could try sign an OAuth application up to a users profile quite easily if they have created one. The attacker would also need to know the victims username and password.

Incorrect Authorization
Improper Authorization in GitHub repository firefly-iii/firefly-iii prior to 5.8.0.

C5 Firefly III CSV Injection.
### Summary
CSV injection is a vulnerability where untrusted user input in CSV files can lead to unauthorized access or data manipulation. 
In my subsequent testing of the application.

### Details
I discovered that there is an option to "Export Data" from the web app to your personal computer, which exports a "csv" file that can be opened with Excel software that supports macros.

P.S 
I discovered that the web application's is offering a demo-site that anyone may access to play with the web application. So, there's a chance that someone will export the data (CVS) from the demo site and execute it on their PC, giving the malicious actor a complete control over their machine. (if a user enters a malicious payload to the website).

### PoC
You can check out my vulnerability report if you need more details/PoC with screenshots: (removed by JC5)

### Impact
An attacker can exploit this by entering a specially crafted payload to one of the fields, and when a user export the csv file using the "Export Data" function, the attacker can potentiality can RCE.

### Addendum by JC5, the developer of Firefly III
There is zero impact on normal users, even on vulnerable versions.