Codecs are the media components that encode and decode audio and video data. In a browser or app, they turn compressed media streams into playable sound and images, and they also create compressed output when recording or transmitting media. Because codecs process complex, attacker-controlled data, they are a common security boundary in media software.
In cyber security, codec bugs matter because a malformed file, stream, or embedded media object can trigger memory corruption, crashes, or other unsafe behavior during parsing and decode. Defenders treat codec code as high risk: they isolate it in sandboxes, fuzz it with unusual media samples, and patch quickly when flaws are found. In practice, securing codecs helps reduce risk from drive-by media content and other payloads delivered through everyday playback features.