Race condition in the Pipe (IPC) close function in FreeBSD 6.3 and 6.4 allows local users to cause a denial of service (crash) or gain privileges via vectors related to kqueues, which triggers a use after free, leading to a NULL pointer dereference or memory corruption.
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.