Why do terminals fail and freeze when outputting a lot of garbage?

Question

PuTTY

I recently encountered such a problem that terminals freeze if a large amount of binary garbage is printed in them. There were two cases. One was when in Wordpress someone decided to print downloaded images for debugging if they could not determine their type, and uploaded it to master. The second is when someone wrote a test using Mockery and without checking it also uploaded it to master. Running these functions throws a lot of garbage into the terminal. If the server is far away (VPS in the data center), then the slow output is understandable, but why does not one of the terminals stand up and hang? By the way, I even ran tests with Mockery locally in Far Manager and it also hangs. What is the reason for the hang? stack overflow? Then stack overflow attack on terminals is possible?

Answer 1

Keyword "control sequences". In particular, ^S ^Q - delay, continue output, etc. Those. among the binary garbage there are symbols or their combinations, which are interpreted by the terminal as commands.