Zero-day and One-day Exploits Rose in 2025, Says VulnCheck
🔍 VulnCheck’s State of Exploitation 2026 report finds 28.96% of known exploited vulnerabilities (KEVs) were exploited before or on the day they were disclosed, up from 23.6% in 2024. In 2025 the firm observed exploitation of 884 vulnerabilities — a 15% year‑over‑year increase — across hundreds of vendors and products. Network edge devices (191 KEVs), content management systems (163) and open source software (129) were the most targeted, while operating systems saw the highest share of zero‑day and one‑day exploits. The report also notes time‑to‑exploitation patterns remained consistent and that ransomware attribution often lagged initial exploit disclosures.
