CVE-2020-29583

What is affected

Vendor	Zyxel
Product	Multiple Products
Weakness	CWE-522

The vulnerability

Zyxel firewalls (ATP, USG, VM) and AP Controllers (NXC2500 and NXC5500) contain a use of hard-coded credentials vulnerability in an undocumented account ("zyfwp") with an unchangeable password.

Required action

Apply updates per vendor instructions.

US federal civilian agencies were required to act by 3 May 2022 under BOD 22-01. The deadline is a compliance date, not a measure of severity — it says nothing about how dangerous the flaw is to anyone else.

Where this comes from

Every field on this page is taken from the CISA Known Exploited Vulnerabilities catalog, last synced 11 Nov 2026, 12:27. Nothing here is our own assessment. For the technical scoring, see the NVD record below.

NVD record ↗ CVE.org record ↗