CVE-2008-1527: Zyxel Prestige 660

High severity, CVSS 7.5. EPSS: 1.4% chance of exploitation in the next 30 days.

ZyXEL Prestige routers, including P-660, P-661, and P-662 models with firmware 3.40(PE9) and 3.40(AGD.2) through 3.40(AHQ.3), support authentication over HTTP via a hash string in the hiddenPassword field, which allows remote attackers to obtain access via a replay attack.

Affected products

• Zyxel Prestige 660: version h-d1 only; version h-d3 only
• Zyxel Prestige 661: version hw-d1 only
• Zyxel Zynos: version 3.40 only

Published 2008-03-26. Last modified 2026-06-16.