Speech-to-text is software that turns spoken audio into written text using automatic speech recognition. It is widely used to transcribe calls, meetings, interviews, and recordings so the content can be searched, indexed, summarized, and analyzed like any other document.
In cyber security, that matters because audio is often a rich source of sensitive information: names, passwords, plans, internal projects, and authentication details can all appear in casual conversation. Attackers can use speech-to-text after a compromise to quickly triage stolen recordings, extract keywords, and feed transcripts into other tools for sorting or summarization. Defenders also use it for monitoring and review, such as converting voicemail or incident-call recordings into text for threat hunting and compliance. The main security concern is not the transcription itself, but how it turns otherwise hard-to-review audio into data that can be searched and exploited at scale.