What’s Vulnerable › Vulnerabilities

CVE-2016-20031: ZKTeco ZKBioSecurity 3.0 Local Authorization Bypass via visLogin.jsp

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-03-16 · updated 2026-06-17
• Weakness: CWE-798

Description

ZKTeco ZKBioSecurity 3.0 contains a local authorization bypass vulnerability in visLogin.jsp that allows attackers to authenticate without valid credentials by spoofing localhost requests. Attackers can exploit the EnvironmentUtil.getClientIp() method which treats IPv6 loopback address 0:0:0:0:0:0:0:1 as 127.0.0.1 and authenticates using the IP as username with hardcoded password 123456 to access sensitive information and perform unauthorized actions.

Affected products

• ZKTeco Inc. ZKTeco ZKBioSecurity: 3.0.1.0_R_230

References

• https://cxsecurity.com/issue/WLB-2016090003
• https://exchange.xforce.ibmcloud.com/vulnerabilities/116488
• https://packetstormsecurity.com/files/138571
• https://www.exploit-db.com/exploits/40327/
• https://www.vulncheck.com/advisories/zkteco-zkbiosecurity-local-authorization-bypass-via-vislogin-jsp
• https://www.zeroscience.mk/en/vulnerabilities/ZSL-2016-5367.php

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