  Dynamic Pushdown Networks (DPNs) are a natural model for multithreaded
programs with (recursive) procedure calls and thread creation. On the other
hand, CARET is a temporal logic that allows to write linear temporal formulas
while taking into account the matching between calls and returns. We consider
in this paper the model-checking problem of DPNs against CARET formulas. We
show that this problem can be effectively solved by a reduction to the
emptiness problem of B\"uchi Dynamic Pushdown Systems. We then show that CARET
model checking is also decidable for DPNs communicating with locks. Our results
can, in particular, be used for the detection of concurrent malware.
