CVE-2020-29583

Known Exploited Public Exploit

Description

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.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 94.33% Top 5%
KEV Since 
Vendor Advisory zyxel.com Vendor Advisory zyxel.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
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/5254/whats-new-for-zld4-60-patch-1-available-on-dec-15 release notes
https://businessforum.zyxel.com/discussion/5252/zld-v4-60-revoke-and-wk48-firmware-release release notes
https://www.eyecontrol.nl/blog/undocumented-user-account-in-zyxel-products.html third party advisory broken link
https://www.zyxel.com/support/CVE-2020-29583.shtml vendor advisory
https://www.secpod.com/blog/a-secret-zyxel-firewall-and-ap-controllers-could-allow-for-administrative-access-cve-2020-29583/ third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2020-29583?
CVE-2020-29583 has been scored as a critical severity vulnerability.
How to fix CVE-2020-29583?
To fix CVE-2020-29583, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-29583 being actively exploited in the wild?
It is confirmed that CVE-2020-29583 is actively exploited. Be extra cautious if you are using vulnerable components. According to its EPSS score, there is a ~94% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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