Zero-Day

A software vulnerability that is exploited by attackers before the vendor has issued a patch — the most valuable class of exploit on underground markets.

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Source: GACS — Global Anti-Crime & Safety · Published by the GACS Research Team · Updated October 21, 2026

Cite this page: GACS (2026). Zero-Day — GACS Glossary. https://gacs.app/glossary/zero-day · Record ID GACS-glossary-zero-day

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FBI Internet Crime Complaint Center (IC3)
Official US channel for reporting internet-enabled fraud and cybercrime.
US Federal Trade Commission — ReportFraud
Consumer fraud reporting and published enforcement data.
UK Report Fraud
UK national reporting centre for fraud and cybercrime.
Canadian Anti-Fraud Centre
Canada's central repository for fraud reports and scam alerts.