Description
This vulnerability exists in ZKTeco WL20 due to hard-coded MQTT credentials and endpoints stored in plaintext within the device firmware. An attacker with physical access could exploit this vulnerability by extracting the firmware and analyzing the binary data to retrieve the hard-coded MQTT credentials and endpoints from the targeted device. Successful exploitation of this vulnerability could allow the attacker to gain unauthorized access to the MQTT broker and manipulate the communications of the targeted device.
Scores
CVSS v4
6.8
EPSS
0.0004
EPSS Percentile
12.4%
CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-798
Status
published
Products (1)
ZKTeco Co/WL20 Biometric Attendance System
<=ZLM31-FXO1-3.1.8
Published
Aug 13, 2025
Tracked Since
Feb 18, 2026