Chip Salzenberg Deliver does not properly associate a lockfile with the user who created the file, which allows local users to cause a denial of service (blockage of incoming e-mail) by creating lockfiles for arbitrary mailboxes.
Concurrent Execution using Shared Resource with Improper Synchronization The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.