CVE-2016-20031

MEDIUM

ZKTeco ZKBioSecurity 3.0 Local Authorization Bypass via visLogin.jsp

Title source: cna
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2016-20031. PoCs published by LiquidWorm.

AI-analyzed exploit summary The vulnerability involves an authorization bypass in ZKTeco ZKBioSecurity 3.0 due to improper handling of the 'EnvironmentUtil.getClientIp(request)' method in visLogin.jsp, which allows local authentication bypass by setting the username to '127.0.0.1' and password to '123456'.

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.

Exploits (1)

exploitdb WRITEUP
by LiquidWorm · textwebappsjsp
https://www.exploit-db.com/exploits/40327

The vulnerability involves an authorization bypass in ZKTeco ZKBioSecurity 3.0 due to improper handling of the 'EnvironmentUtil.getClientIp(request)' method in visLogin.jsp, which allows local authentication bypass by setting the username to '127.0.0.1' and password to '123456'.

Classification
Writeup 90%
Attack Type
Auth Bypass
Complexity
Trivial
Reliability
Reliable
Target: ZKTeco ZKBioSecurity 3.0 (visLogin.jsp)
No auth needed
Prerequisites: Access to the login page · IP address manipulation to trigger the bypass condition
devstral-2 · analyzed Mar 16, 2026 Full analysis →

References (6)

Core 6
Core References
Third Party Advisory third-party-advisory
Zero Science Lab Disclosure
https://www.zeroscience.mk/en/vulnerabilities/ZSL-2016-5367.php
Third Party Advisory third-party-advisory
CXSecurity
https://cxsecurity.com/issue/WLB-2016090003
Vdb Entry vdb-entry
IBM X-Force Exchange
https://exchange.xforce.ibmcloud.com/vulnerabilities/116488
Exploit exploit
Packet Storm Security
https://packetstormsecurity.com/files/138571
Exploit exploit
Reference
https://www.exploit-db.com/exploits/40327/
Third Party Advisory third-party-advisory
VulnCheck Advisory: ZKTeco ZKBioSecurity 3.0 Local Authorization Bypass via visLogin.jsp
https://www.vulncheck.com/advisories/zkteco-zkbiosecurity-local-authorization-bypass-via-vislogin-jsp

Scores

CVSS v3 5.5
EPSS 0.0015
EPSS Percentile 4.5%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-798
Status published
Products (1)
ZKTeco Inc./ZKTeco ZKBioSecurity 3.0.1.0_R_230
Published Mar 16, 2026
Tracked Since Mar 16, 2026