CVE-2019-15799

Name: CVE-2019-15799
Creator: NVD / NIST
Published: 2019-11-14T21:15:11.623+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 2.31%

Last modified Jun 17, 2026

CVE-2019-15799 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. User accounts created through the web interface of the device, when given non-admin level privileges, have the same level of privileged access as administrators when connecting to the device via SSH (while their permissions via the web interface are in fact restricted). EPSS estimates a 2.31% chance of exploitation in the next 30 days.

Description

An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. User accounts created through the web interface of the device, when given non-admin level privileges, have the same level of privileged access as administrators when connecting to the device via SSH (while their permissions via the web interface are in fact restricted). This allows normal users to obtain the administrative password by running the tech-support command via the CLI: this contains the encrypted passwords for all users on the device. As these passwords are encrypted using well-known and static parameters, they can be decrypted and the original passwords (including the administrator password) can be obtained.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

2.31%

81.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-269

Affected Software

Vendor	Product	Versions
Zyxel	Gs1900-8 Firmware	< 2.50\(aahh.0\)c0
Zyxel	Gs1900-8hp Firmware	< 2.50\(aahi.0\)c0
Zyxel	Gs1900-10hp Firmware	< 2.50\(aazi.0\)c0
Zyxel	Gs1900-16 Firmware	< 2.50\(aahj.0\)c0
Zyxel	Gs1900-24e Firmware	< 2.50\(aahk.0\)c0
Zyxel	Gs1900-24 Firmware	< 2.50\(aahl.0\)c0
Zyxel	Gs1900-24hp Firmware	< 2.50\(aahm.0\)c0
Zyxel	Gs1900-48 Firmware	< 2.50\(aahn.0\)c0
Zyxel	Gs1900-48hp Firmware	< 2.50\(aaho.0\)c0

References

https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.htmlExploit, Third Party Advisory
https://vimeo.com/354726424Exploit, Third Party Advisory
https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtmlVendor Advisory
https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.htmlExploit, Third Party Advisory
https://vimeo.com/354726424Exploit, Third Party Advisory
https://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtmlVendor Advisory

Timeline

Published: Nov 14, 2019
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-15799?

How severe is CVE-2019-15799?

CVE-2019-15799 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 2.31% probability of exploitation in the next 30 days.

How do I fix CVE-2019-15799?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2019-15799?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST