Just got in and found all your emails, thanks to everyone for the help!

Since I was on the road most of the day, I didn't have time to do much other than put a few drops of oil on the pivot posts and work the (released) brake arms a bit which seemed to do the job. Since the weather had been humid and I did catch some rain during the past week, maybe there was some water egress in the pivot posts causing some binding and today's low temperature might have been coincidental. So far the brakes are working fine, and I will take the time to disassemble, clean and grease them during the weekend.

As for the cables, they're the stock original cables which came with the bike, so I can't tell you if they'e greased or not.


Edit: Can you recommend a specific type of grease?