OSV is a machine-readable vulnerability format for open-source security data. It represents a flaw in a structured way, usually with fields such as the affected package, vulnerable versions, severity, references, and fixed versions. Because the data is standardized, tools can read and exchange it without manual reformatting.
This matters in cyber security because open-source dependencies are reused everywhere, and a small change can affect many products. OSV records help scanners, package managers, SBOM tools, and vulnerability databases speak the same language. In real defenses, teams use OSV feeds to flag exposed builds, prioritize patching, and automate alerts. In attacks, adversaries benefit when defenders do not know which versions are affected; OSV helps close that gap by making exposure faster to identify and act on.