Berliner Tageszeitung - Why You Need to Audit Your Cloud Storage Links Immediately

The convenience of cloud storage has fundamentally changed how individuals and businesses handle data. When hardware fails, such as a laptop being damaged by liquid, cloud services like Google Drive, OneDrive, and iCloud often serve as the primary backup for critical work. Similarly, the method of transferring large files has shifted from physical media, such as USB drives or postal mail, to digital links that allow instant global sharing.

However, this ease of distribution introduces persistent security risks. Shared links can inadvertently reach unintended recipients through forwarded emails or compromised contact accounts. Once a link is active, anyone with the URL can potentially view, modify, or delete files, depending on the permissions granted at the time of sharing. While these services employ robust default protections, the longevity of a shared link correlates directly with the probability of exposure.

Security professionals recommend conducting regular audits of active cloud links to mitigate these risks. Revoking access is straightforward across most major platforms, though the tools available vary significantly by service provider.

For Microsoft OneDrive users, the web portal offers a centralized view of shared content. By selecting "Shared link" in the left navigation pane and filtering by "By you," users can view all files they have distributed. Sorting by the "Modified" header helps identify older links that may no longer be necessary. To manage access, users click the three-dot menu next to a file and select "Manage access." This allows for the removal of specific individuals or the complete deletion of link-based sharing via the trash icon. Additionally, OneDrive allows users to set expiration dates for new shares, automatically revoking access after a specified period.

Apple’s iCloud Drive provides similar management capabilities but lacks some organizational features. Users can navigate to the "Shared" section in the web interface to view distributed files. While there is no native sorting function for these lists, the search bar can locate specific items. Access control is managed through the "Manage Shared File" option, which permits users to block specific contacts, adjust permissions between viewing and editing, or stop sharing entirely. Unlike OneDrive, iCloud does not support automatic expiration dates for shared links, requiring manual intervention to close access.

Dropbox takes a more proactive approach to link management. The service frequently prompts users to review shared files and folders through its applications. On the web portal, the "Shared" pane provides a detailed breakdown of active connections, categorized by file or folder type. Users can remove individual contacts or use the "Unshare" button to terminate all access simultaneously. Dropbox also includes built-in link expiry features, allowing users to set time limits on new shares, provided recipients view the content within that window.

Google Drive presents a more fragmented experience for managing shared links. The web interface does not offer a direct list of all publicly shared items. Instead, users must utilize the "People" filter to view files shared with specific contacts or select "Anyone with the link" from the dropdown menu to see open connections. Sharing settings can be adjusted via the three-dot menu and the share panel, where users can remove contacts or disable the visible link. However, Google Drive lacks a native expiration date feature for shared links, meaning access must be manually revoked by the owner.

The disparity in features across these platforms highlights the need for user vigilance. While some services automate the cleanup process through expiration dates, others rely entirely on manual audits. Given that old links can remain active indefinitely, regular review of sharing settings is essential to maintain data privacy and prevent unauthorized access.

L. Andersson--BTZ