ZKTeco ZKBioSecurity 3.0 contains a user enumeration vulnerability in the authLoginAction!login.do script, allowing unauthenticated attackers to disco...
Description
ZKTeco ZKBioSecurity 3.0 contains a user enumeration vulnerability in the authLoginAction!login.do script, allowing unauthenticated attackers to discover valid usernames.
AI Analyst Comment
Remediation
Update Unknown Multiple Products to the latest version. Monitor for exploitation attempts and review access logs.
---METADATA---
VENDOR: ZKTeco
PRODUCT: ZKBioSecurity
AFFECTED_VERSIONS: 3.0
---END_METADATA---
Description Summary:
ZKTeco ZKBioSecurity 3.0 contains a user enumeration vulnerability in the authLoginAction!login.do script, allowing unauthenticated attackers to discover valid usernames.
Executive Summary:
An unauthenticated user enumeration vulnerability in ZKTeco ZKBioSecurity 3.0 facilitates targeted brute-force attacks by allowing attackers to identify valid system accounts.
Vulnerability Details
CVE-ID: CVE-2016-20030
Affected Software: ZKTeco ZKBioSecurity
Affected Versions: 3.0
Vulnerability: The application fails to mask differences in responses when partial characters are submitted to the username parameter in the login script. This allows an unauthenticated attacker to systematically discover valid usernames through the
authLoginAction!login.doscript.Business Impact
While user enumeration is often seen as a precursor, the CVSS score of 9.8 indicates this vulnerability is part of a critical risk chain. Discovering valid usernames significantly reduces the complexity of brute-force or credential-stuffing attacks, leading to unauthorized access to security management systems. This could result in the compromise of physical security logs and access controls.
Remediation Plan
Immediate Action: Update ZKBioSecurity to the latest version or apply patches that normalize authentication responses to prevent account discovery.
Proactive Monitoring: Review authentication logs for high volumes of failed login attempts or systematic username variations originating from a single IP address.
Compensating Controls: Implement account lockout policies and multi-factor authentication (MFA) to mitigate the risk of attackers successfully using discovered usernames.
Exploitation Status
Public Exploit Available: No
Analyst Notes: As of March 16, 2026, there is no public information indicating active exploitation. This is a late disclosure of a 2016 vulnerability, suggesting that legacy systems remain at significant risk.
Analyst Recommendation
Organizations using ZKTeco ZKBioSecurity 3.0 must update their installations immediately to prevent attackers from mapping out valid user accounts. Given the critical severity rating, this should be treated as a high-priority task to protect the integrity of the organization's security infrastructure.