CVE-2016-20031
Medium
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.
SeverityMedium
CVSS5.5
Exploit probability—
ProductZKTeco ZKBioSecurity
PublishedMar 16, 2026
First seenMar 16, 2026
Weakness typeCWE-798Hard-coded credentials
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| ZKTeco Inc. ZKTeco ZKBioSecurity | 3.0.1.0_R_230 | — |
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