CVE-2019-15803

Published Nov 14, 2019

Last updated 4 years ago

Overview

Description
An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. Through an undocumented sequence of keypresses, undocumented functionality is triggered. A diagnostics shell is triggered via CTRL-ALT-t, which prompts for the password returned by fds_sys_passDebugPasswd_ret(). The firmware contains access control checks that determine if remote users are allowed to access this functionality. The function that performs this check (fds_sys_remoteDebugEnable_ret in libfds.so) always return TRUE with no actual checks performed. The diagnostics menu allows for reading/writing arbitrary registers and various other configuration parameters which are believed to be related to the network interface chips.
Source
cve@mitre.org
NVD status
Analyzed

Risk scores

CVSS 3.1

Type
Primary
Base score
9.1
Impact score
5.2
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Severity
CRITICAL

CVSS 2.0

Type
Primary
Base score
6.4
Impact score
4.9
Exploitability score
10
Vector string
AV:N/AC:L/Au:N/C:P/I:P/A:N

Weaknesses

nvd@nist.gov
CWE-287

Social media

Hype score
Not currently trending

Configurations