AEGLIX vulnerability intelligence
CVE-2020-29583
CRITICAL · CVSS 9.8 · Analyzed
Published: 2020-12-22 · Updated: 2026-06-17 · Source: NVD
Vulnerability overview
Firmware version 4.60 of Zyxel USG devices contains an undocumented account (zyfwp) with an unchangeable password. The password for this account can be found in cleartext in the firmware. This account can be used by someone to login to the ssh server or web interface with admin privileges.
Severity and scoring
- CVSS score
- 9.8 · CRITICAL
- CVSS version
- 3.1
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-522
CVSS measures technical severity; it does not establish whether this vulnerability is being exploited in your environment.
Known exploitation and remediation
Listed in CISA’s Known Exploited Vulnerabilities catalog.
- Affected product
- Zyxel · Multiple Products
- Added to catalog
- 2021-11-03
- Required action
- Apply updates per vendor instructions.
- CISA remediation due date
- 2022-05-03
CISA deadlines apply to the organizations covered by its directives. Confirm your own remediation requirements.
Verify affected versions and patch availability in the vendor advisory before making changes.
Affected products and versions
cpe:2.3:o:zyxel:usg20-vpn_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg20w-vpn_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg40_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg40w_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg60_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg60w_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg110_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg210_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg310_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg1100_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg1900_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg2200_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:zywall110_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:zywall310_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:zywall1100_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp100_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp100w_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp200_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp500_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp700_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp800_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn50_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn100_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn300_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn1000_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_100_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_100w_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_200_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_500_firmware:4.60:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_700_firmware:4.60:*:*:*:*:*:*:*
These are NVD CPE applicability entries. Some products depend on configuration conditions; consult the official record to confirm applicability.
Advisories and references
- http://ftp.zyxel.com/USG40/firmware/USG40_4.60%28AALA.1%29C0_2.pdf
Broken Link
- https://businessforum.zyxel.com/discussion/5252/zld-v4-60-revoke-and-wk48-firmware-release
Release Notes
- https://businessforum.zyxel.com/discussion/5254/whats-new-for-zld4-60-patch-1-available-on-dec-15
Release Notes
- https://www.eyecontrol.nl/blog/undocumented-user-account-in-zyxel-products.html
Broken Link · Third Party Advisory
- https://www.secpod.com/blog/a-secret-zyxel-firewall-and-ap-controllers-could-allow-for-administrative-access-cve-2020-29583/
Exploit · Third Party Advisory
- https://www.zyxel.com/support/CVE-2020-29583.shtml
Vendor Advisory
- https://www.zyxel.com/support/security_advisories.shtml
Vendor Advisory
- http://ftp.zyxel.com/USG40/firmware/USG40_4.60%28AALA.1%29C0_2.pdf
Broken Link
- https://businessforum.zyxel.com/discussion/5252/zld-v4-60-revoke-and-wk48-firmware-release
Release Notes
- https://businessforum.zyxel.com/discussion/5254/whats-new-for-zld4-60-patch-1-available-on-dec-15
Release Notes
- https://www.eyecontrol.nl/blog/undocumented-user-account-in-zyxel-products.html
Broken Link · Third Party Advisory
- https://www.secpod.com/blog/a-secret-zyxel-firewall-and-ap-controllers-could-allow-for-administrative-access-cve-2020-29583/
Exploit · Third Party Advisory
- https://www.zyxel.com/support/CVE-2020-29583.shtml
Vendor Advisory
- https://www.zyxel.com/support/security_advisories.shtml
Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-29583
US Government Resource