Decrypting Locally Stored Firefox Passwords

Welcome to our blog post on decrypting locally stored Firefox passwords! In this article, we will explore the process of decrypting passwords saved in Mozilla Firefox’s local storage. Please note that this information is intended for educational purposes only.

Disclaimer: Decrypting passwords without proper authorization is illegal and unethical. This article is meant to increase awareness about the technical aspects involved, not to encourage unauthorized access to personal information.

Background

When Firefox users choose to save their passwords for various websites, the browser securely stores them locally in a file known as “logins.json”. These passwords are encrypted to protect users’ sensitive information.

Let’s first save a password in Firefox:

Windows: C:/Users//AppData/Roaming/Mozilla/Firefox/Profiles
Mac: ~/Library/Application Support/Firefox/Profiles

In our case it is located under:

C:\..\Profiles\m8zymk5c.default-release

The Encryption Process

Firefox uses a combination of symmetric and asymmetric encryption to protect stored passwords. The user’s master password, set by the user, serves as the key to decrypting the stored passwords.

First, Firefox generates a random 256-bit encryption key known as the “data encryption key” (DEK). This key is then used to encrypt the passwords stored in “logins.json”. The DEK is further encrypted using the user’s master password, which serves as the key to the key.

When the user attempts to access their stored passwords, they are prompted to enter their master password. Firefox then uses the master password to decrypt the DEK, which is in turn used to decrypt the passwords stored in “logins.json”.

Decrypting Locally Stored Passwords

To decrypt locally stored Firefox passwords, follow these steps:

1. Locate the “logins.json” file on the user’s system. This file is typically found in the Firefox profile directory.
2. Open the “logins.json” file using a text editor or a JSON viewer.
3. Search for the entry corresponding to the desired website’s login credentials.
4. Extract the encrypted password from the entry.
5. Prompt the user for their master password.
6. Decrypt the DEK using the entered master password.
7. Decrypt the encrypted password using the decrypted DEK.
8. Display the decrypted password to the user (or use it as needed, considering legal and ethical boundaries).

Important: Always ensure you have proper authorization and follow legal and ethical guidelines before attempting to decrypt passwords. Unauthorized access to personal information is a serious offense.

In this blog we are going to use a python script firefox_decrypt.py written by Renato Alves

python firefox_decrypt.py

Conclusion

Decrypting locally stored Firefox passwords involves understanding the encryption process used by the browser and properly decrypting the stored passwords using the user’s master password. However, it is essential to emphasize that unauthorized access to personal information is illegal and unethical.

We hope this article has provided you with valuable insights into the technical aspects of decrypting locally stored Firefox passwords. Remember to use this knowledge responsibly and ethically, always respecting user privacy and abiding by the law.