Might have a memory leak when running ckproxy. Had a Pi start acting up this morning after running fine for about 3 weeks. Turned out it ran out of free memory and the watchdog had trouble killing it and killed some system processes instead. Checked the other Pis and the ckproxy process was using high amounts of memory. Percentage-wise the memory on most of them had gone over 60%, where on a fresh start it's more around 6-7%.
There could well be, especially if you're running older code. Try running latest git if you haven't upgraded lately as the code has been dramatically updated. When time permits I'll do a more extensive search for memleaks with the proxy code.