Discord makes file links temporary to fight abuse
Discord plans to introduce a fundamental change to the service's file hosting and linking functionality by the end of 2023. One of the main goals of the change is to limit abuse of the service for malicious and other undesirable purposes.
When users upload files on Discord, they may also publish links that point to these files elsewhere on the Internet. Since this is free, all that is required is an account, it has been abused by malware campaigns, for distributing copyrighted content and for using Discord as a cheap file hosting service.
A report by cybersecurity company Trellix published last month claimed that it discovered about 10,000 malware samples on Discord's CDN. Discord has file size limits, but this is the only restriction in regards to the feature.
The introduction of temporary file links impacts externally posted links only. Basically, what Discord plans to do is update file links every 24 hours. Links posted on Discord will be redirected automatically to the new target, so that nothing changes for users of the service who access links internally.
Links that point to the original file location will return a not found error, on the other hand. In other words: links from outside of Discord that point to files hosted by the service will expire after 24 hours, which will reduce the effectiveness of malware campaigns and other sorts of abuse of the system.
All Discord CDN urls will get new parameters that include expiration timestamps and unique signatures. This prevents that Discord is used as a permanent file host.
Clearly, there are still ways to go around the limit. Discord users could upload files anew and update links, or look for the updated link to update it on third-party sites as well. Malware campaigns last for a short time only in some cases, which might mean that these short-lived campaigns are not affected by the change.
Still, Discord's new temporary file links system will impact malware and also the use of it for file sharing significantly. Files that are malicious or abusive may also be removed entirely from the servers by the team. Some legitimate users of Discord may be impacted by the change. If users host links to files on Discord elsewhere, they will also notice that the links won't work anymore after the change takes effect.
Now You: do you use Discord?