Side-Channel

旁敲侧击 (páng qiāo cè jī): Side-knock

Side-channel vulnerabilities can be due to algorithmic or protocol weaknesses, flaws or lacks, implementation bugs, lack of defensive processing or all the mentioned.

Beware of little expenses, a small leak will sink a great ship. — Benjamin Franklin (January 6, 1706 — April 17, 1790), Poor Richard’s Almanack, 1745

Analysis

Attackers exploit covert channels to leak messages across security boundaries. Side channels are covert channels signaling performed unexpectedly.