Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability in Apache Answer. This issue affects Apache Answer: through 1.2.0. Under normal circumstances, a user can only bookmark a question once, and will only increase the number of questions bookmarked once. However, repeat submissions through the script can increase the number of collection of the question many times. Users are recommended to upgrade to version [1.2.1], which fixes the issue.