Is CVE-2016-20031 actively exploited?

CVE-2016-20031 has no public evidence of in-the-wild exploitation as of 2026-04-15.

What is the CVSS score for CVE-2016-20031?

CVE-2016-20031 has a CVSS score of 6.8 (MEDIUM severity). Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X.

How do I patch CVE-2016-20031?

Vendor patch guidance is linked from the references on this page. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2016-20031.

Which products are affected by CVE-2016-20031?

Affected products for CVE-2016-20031 are listed on this page once vendor data becomes available.

CVE-2016-20031 - remediation guidance & executive summary

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.

CVSS Metrics

Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector: local
Complexity: low
Privileges: low
User Action: none
Confidentiality: undefined
Integrity: undefined
Availability: undefined
Weaknesses: CWE-798 · Hard-coded Credentials

Metadata

Primary Vendor: UNKNOWN
Published: 3/16/2026
Last Modified: 4/15/2026
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

CVE-2016-20031

Description

CVSS Metrics

Metadata

Affected Products

Remediation Guidance

Executive Summary