The issue was with the Google Takeout feature - which lets Google Photo users export content of their accounts - and lasted for four days in November last year.
Google has clarified that users either received an incomplete archive, or videos which belonged to strangers.
Although the company declined to say how many people were affected, a spokesman told the BBC it was "less than 0.01%" of the platform's one billion users, while only videos were impacted rather than photos or other data.
The tech giant added in a statement: "We fixed the underlying issue and have conducted an in-depth analysis to help prevent this from ever happening again.
"We are very sorry this happened."
In a note sent to users, Google opened up about the bug and advised further action.
The message read: "If you downloaded your data, it may be incomplete, and it may contain videos that are not yours.
"The underlying issue has been identified and resolved. We recommend you perform another export of your content and delete your prior export at this time."