Zyxel Multiple Products
YES - ON THE CISA KEV LIST
CVE-2020-29583
Zyxel Multiple Products Use of Hard-Coded Credentials Vulnerability
overdue since 2022-05-03
Zyxel: 13 entries (0.7% of all KEV entries are from this vendor); 1 added in 2026.
BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.
Your BOD 26-04 window (SSVC tier helper)
Your remediation window ends:
Description
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 (CISA)
Apply updates per vendor instructions.
Notes
https://nvd.nist.gov/vuln/detail/CVE-2020-29583
References
Other KEV entries for this vendor: Zyxel
- CVE-2026-7273 - GS1900 Series Switches (2026-09-21)
- CVE-2024-40891 - DSL CPE Devices (2025-02-11)
- CVE-2024-40890 - DSL CPE Devices (2025-02-11)
- CVE-2024-11667 - Multiple Firewalls (2024-12-03)
- CVE-2017-6884 - EMG2926 Routers (2023-09-18)
- CVE-2017-18368 - P660HN-T1A Routers (2023-08-07)
- CVE-2023-27992 - Multiple Network-Attached Storage (NAS) Devices (2023-06-23)
- CVE-2023-33009 - Multiple Firewalls (2023-06-05)
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