Speculation about ISIS having surface-to-air missiles appears to be answered this weekend, with British Lt. Gen. Mark Carleton-Smith saying that British warplanes over Iraq have been fired at by such missiles coming from ISIS targets recently.
According to the general, the British planes detected such launches from the ground, but so far none of them had any material effect on the planes themselves, nor forced any change in tactics in the ongoing air war against ISIS targets.
ISIS forces in Syria are believed to have acquired some surface-to-air missiles that were provided as part of the CIA effort to arm Syrian rebel groups, as such weapons quickly ended up distributed around to several different groups.
ISIS is also said to be trying to develop its own missiles for this purpose, trying to convert old air-to-air missiles they’ve looted into something that could be fired from the ground at attacking warplanes. Again, there is as yet no evidence what sort of missiles ISIS has fired at the British planes.