Dangers of URL shortening

CC BY-ND by Zoolcar9

Two researchers have looked at the risk of the use of short URLs , such as those generated by Google, Microsoft and bit.ly. See this pdf It appears that the shortened links, sometimes areonly six characters long, are easy to guess, just by trying lots of combinations. In some cases, the short links are used to share files in Google Drive and Microsoft Onedrive, and researchers found files that were linked to directories with write access, so that it became possible to (potentially malicious) write files in the cloud storage of strangers.

Because much of what is stored in the cloud, is also synchronized with the desktop, it would be possible in this way to infect PCs with malware.
According to the researchers 7% of the scanned Microsoft OneDrive and Google Drive accounts were  sensitive for this hack.
They laid hands on potentially sensitive information via short links to routes such as Google Maps. Routes gave information about people free; such as the addresses they visited, and there were medical and religious institutions, pawnshops and juvenile prisons in.

People think they are safe because no one else knows the link, but the researchers have to assume that anybody who uses URL shorteners is at risk. Therefore, they find it generated short links as a very bad idea for all in the cloud.

In response, Google has doubled the number of characters used, and Microsoft shorting link function removed from OneDrive.