At the time of writing, the issue appears to be related to a buffer management issue in the exFAT file system driver.
There are no similar issues on other more popular file systems.
This issue relates to the underlying exFAT filesystem where the backups are stored and can impact any Veeam products capable of storing backup files on such filesystem.
Veeam is working closely with Microsoft support to investigate this issue.
This article will be updated as further information becomes available.