Google disclosed Saturday that it shared a very small number of online documents with users who weren't authorized to see them.
The privacy glitch, caused by a software bug, affected just a tiny fraction of documents — an estimated less than 0.05 percent — wrote Jennifer Mazzon, Google Docs product manager, on a corporate blog.
Google notified users affected by the bug on Friday and reversed the mistake, she said.
The bug hit users who changed their sharing settings on multiple presentations and documents at once, causing Google to share those documents with other users with whom the document owner had shared a document before, Mazzon wrote.
Though contained, the mistake underscores another pitfall of online software: the chance that someone may gain unintentional access to it.