CVE-2004-1540: Zyxel Prestige

Medium severity, CVSS 5.0. EPSS: 6.6% chance of exploitation in the next 30 days.

ZyXEL Prestige 623, 650, and 652 HW Routers, and possibly other versions, with HTTP Remote Administration enabled, does not require a password to access rpFWUpload.html, which allows remote attackers to reset the router configuration file.

Affected products

• Zyxel Prestige: version 645r_a1 only; version 650h only; version 650hw only; version 650hw_31 only; version 650r only
• Zyxel Zynos: version 3.40 only; version is.3 only; version is.5 only

Published 2004-12-31. Last modified 2026-06-16.