Attention: We have transitioned to a new AAD or Microsoft Entra ID from the week of May 20, 2024. In case your tenant requires admin consent, please refer to this document located at Overview of user and admin consent - Microsoft Entra ID | Microsoft Learn and grant access to App ID: 6ba09155-cb24-475b-b24f-b4e28fc74365 with graph permissions for Directory.Read.All and User.Read for continued access. While the app may appear unverified, you can confirm its legitimacy by verifying the App ID provided.
Trojan:JS/Medfos.A is a malicious JavaScript that redirects search queries when you use search engines. It is installed as a malicious Mozilla Firefox extension.
To detect and remove this threat and other malicious software that may be installed on your computer, run a full-system scan with an appropriate, up-to-date, security solution. The following Microsoft products detect and remove this threat:
You can also remove the malicious add-on by following these instructions from Mozilla.
Threat behavior
Installation
Trojan:JS/Medfos.A is typically installed by Trojan:Win32/Medfos.B as a Mozilla Firefox extension. It is usually installed in the file "%LOCALAPPDATA%\(random CLSID)\chrome\content\browser.xul".
If this extension is installed, it may have use any of the following names:
Translate This! 2.0
Mozilla Safe Browsing 2.0.14
Mozilla Framework Assistant 3.0.1
Payload
Redirects Mozilla Firefox
When browsing using Mozilla Firefox, this malware may redirect you from the URL that you type in, if you are trying to visit the AOL, Ask, Bing, Google, or Yahoo websites. It may redirect you to websites such as the following:
