In context: Few file-sharing services are as convenient as Firefox Send. While it does have a relatively low file size cap, it's still a popular tool for safely transferring content between friends, thanks to its automatic file destruction functionality and encryption.

Unfortunately for fans of the service (myself included), Firefox Send has been down lately. If you've attempted to visit the Send website anytime in the past week, you probably saw the following message in place of the traditional file uploading options:

Firefox Send is temporarily unavailable while we work on product improvements.

We appreciate your patience while we make the Firefox Send experience better.

It wasn't immediately clear what product improvements Mozilla was referring to. Send worked just fine, and mere feature upgrades generally don't require full service stoppage. However, thanks to a recent report from ZDNet, we now have a much better idea of what's going on.

Apparently, Mozilla decided to temporarily shut down Send in response to the outlet's inquiries about its "increasing prevalence in current malware operations." ZDNet says Send has been used to spread "payloads" for a variety of cybercrime operations, ranging from "ransomware to financial crime."

While one might argue that taking down an entire file-sharing service to counter a few bad actors is overkill, it does give Send's developers time to add helpful anti-abuse features without letting viruses run rampant.

As an example of such a feature, Send will receive an "abuse reporting mechanism" during its hiatus, which will let users draw the company's attention to risky files. Additionally, users will no longer be able to share files with full anonymity -- when Send returns, you'll be required to sign in with a Firefox account to upload content.

We are not sure when Firefox Send will be brought back online, but we'll update this article if that day comes soon.