ZKTeco WL20 Biometric Attendance System up to 3.1.8 hard-coded credentials

Summaryinfo

A vulnerability was found in ZKTeco WL20 Biometric Attendance System up to 3.1.8. It has been classified as critical. Affected by this vulnerability is an unknown functionality. This manipulation causes hard-coded credentials. This vulnerability is handled as CVE-2025-55279. It is feasible to perform the attack on the physical device. There is not any exploit available.

Detailsinfo

A vulnerability has been found in ZKTeco WL20 Biometric Attendance System up to 3.1.8 and classified as critical. Affected by this vulnerability is an unknown code block. The manipulation with an unknown input leads to a hard-coded credentials vulnerability. The CWE definition for the vulnerability is CWE-798. The product contains hard-coded credentials, such as a password or cryptographic key, which it uses for its own inbound authentication, outbound communication to external components, or encryption of internal data. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

This vulnerability exists in ZKTeco WL20 due to hard-coded private key 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 private key stored in the firmware of the targeted device. Successful exploitation of this vulnerability could allow the attacker to perform unauthorized decryption of sensitive data and Man-in-the-Middle (MitM) attacks on the targeted device.

The weakness was released by Shravan Singh as CIVN-2025-0172. It is possible to read the advisory at cert-in.org.in. This vulnerability is known as CVE-2025-55279 since 08/12/2025. The exploitation appears to be easy. Attacking locally is a requirement. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1110.001 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Type

• Router Operating System

Vendor

• ZKTeco

Name

• WL20 Biometric Attendance System

Version

• 3.1.0
• 3.1.1
• 3.1.2
• 3.1.3
• 3.1.4
• 3.1.5
• 3.1.6
• 3.1.7
• 3.1.8

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

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• 🔒
• 🔒

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