CVE-2019-15804

Name: CVE-2019-15804
Creator: NVD / NIST
Published: 2019-11-14T21:15:11.953+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.93%

Last modified Jun 17, 2026

CVE-2019-15804 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. By sending a signal to the CLI process, undocumented functionality is triggered. EPSS estimates a 0.93% 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. By sending a signal to the CLI process, undocumented functionality is triggered. Specifically, a menu can be triggered by sending the SIGQUIT signal to the CLI application (e.g., through CTRL+\ via SSH). The access control check for this menu does work and prohibits accessing the menu, which contains "Password recovery for specific user" options. The menu is believed to be accessible using a serial console.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

0.93%

56.1th percentile

Probability of exploitation in the next 30 days. Learn more

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://www.zyxel.com/support/gs1900-switch-vulnerabilities.shtmlVendor Advisory
https://jasper.la/exploring-zyxel-gs1900-firmware-with-ghidra.htmlExploit, 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-2019-15804?

How severe is CVE-2019-15804?

CVE-2019-15804 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.93% probability of exploitation in the next 30 days.

How do I fix CVE-2019-15804?

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-2019-15804?

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

Scan your code now

Source: NVD / NIST