Mozilla has temporarily suspended the file sharing service due to its involvement in the distribution of malware and complaints about the lack of means to send abuse notifications regarding improper use of the service (there was only a general feedback form). Work is planned to be restored after the implementation of the ability to report the placement of malicious or problematic content, as well as establishing a service for prompt responses to such messages. There are also plans to disable anonymous file sharing — uploading a file to the service will require registering an account via the Firefox Account service.
As a reminder, Firefox Send allowed users to upload a file to Mozilla's servers in anonymous mode with a limit of up to 1 GB and 2.5 GB when creating a registered account. On the browser side, the file was encrypted and sent to the server already in encrypted form. After uploading the file, the user was provided with a link that was generated on the client side and included an identifier and key for decryption. Using the provided link, the recipient could download the file and decrypt it on their side. The sender had the option to set the number of downloads after which the file would be deleted from Mozilla's storage, as well as the file's lifetime (from one hour to 7 days).
Recently, Firefox Send has become popular among malicious actors as malware, storing components used for various attacks, and data intercepted as a result of malware operations or the compromise of user systems. The popularity of the service among malicious actors was aided by the support for data encryption and content protection via passwords in Firefox Send, as well as the ability for files to be automatically deleted after a certain number of downloads or after a specified lifetime, which complicated the investigation of malicious activities and allowed for the evasion of attack detection systems. Additionally, links to the domain send.firefox.com in emails were generally considered trustworthy and were not blocked by anti-spam filters.
Source: opennet.ru
