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🕳️

Zero‑Day

Threats

Incident Response Exploit Patch (Security Update) Security Audit

A security bug with no fix yet.

Definition

A zero‑day is a vulnerability that is unknown to the vendor or not fixed yet, so attackers can exploit it before a patch exists.

In plain English A security bug with no fix yet.

Why this matters

Why it matters: Zero‑days can enable silent hacks that expose private data.

Example

Example: An attacker uses an unpatched bug to access devices.