Infinite synchronization loop of an infected file from a cloud storage
ESET Customer Advisory 2016-0013
September 21, 2016
ESET was made aware that users of cloud synchronization applications, such as Dropbox or OneDrive, noticed a loop of unsuccessful synchronization attempts when their cloud storage contained an infected file. ESET prepared a fixed Antivirus and antispyware scanner module which resolves this behavior.
When a cloud storage contained an infected file, the synchronization application tried to download it to the user’s computer. Before it managed to move the file to the actual destination directory, ESET product installed on the computer detected the infected file in the application’s cache and removed it. Thus, the synchronization attempt was considered to be unsuccessful and the application tried to download the file again. This went on endlessly. With the fixed Antivirus and antispyware scanner module, ESET product first lets the application to finish downloading, move the file from its cache to the destination directory and mark the synchronization attempt as successful, and only then it removes the file from the synchronized folder, which invokes a separate synchronization and the file is then correctly removed from the cloud storage as well.
The fixed Antivirus and antispyware scanner module version 1501 was released to the pre-release channel on September 20, 2016 and on September 22, 2016 it was released for all users (both consumer and business segment).
Users affected by this issue may wait till the fixed module is released publically and downloaded automatically to their computer, or may switch to the pre-release channel and have the module downloaded immediately.
Note: The fixed Antivirus and antispyware scanner module version 1501 won’t resolve the issue for users of ESET Smart Security and ESET NOD32 Antivirus version 9.0.402. An updated module which resolves the issue for this specific version will be released in the upcoming days.
Feedback & Support
Version 1.1 (September 22, 2016): Antivirus and antispyware scanner module version 1501 released for all users
Version 1.0 (September 21, 2016): Initial version of this document