ZKTeco ZKBioSecurity 3.0.1.0_R_230 User Account authLoginAction!login.do Username incorrect behavior order

CVSS Meta Temp Score
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CTI Interest Score
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8.4$0-$5k0.00

Summaryinfo

A vulnerability was found in ZKTeco ZKBioSecurity 3.0.1.0_R_230. It has been rated as critical. The impacted element is an unknown function of the file authLoginAction!login.do of the component User Account Handler. This manipulation of the argument Username causes incorrect behavior order. This vulnerability is tracked as CVE-2016-20030. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as critical was found in ZKTeco ZKBioSecurity 3.0.1.0_R_230. Affected by this vulnerability is an unknown function of the file authLoginAction!login.do of the component User Account Handler. The manipulation of the argument username with an unknown input leads to a incorrect behavior order vulnerability. The CWE definition for the vulnerability is CWE-551. If a web server does not fully parse requested URLs before it examines them for authorization, it may be possible for an attacker to bypass authorization protection. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

ZKTeco ZKBioSecurity 3.0 contains a user enumeration vulnerability that allows unauthenticated attackers to discover valid usernames by submitting partial characters via the username parameter. Attackers can send requests to the authLoginAction!login.do script with varying username inputs to enumerate valid user accounts based on application responses.

The weakness was disclosed by Gjoko Krstic as ZSL-2016-5366. It is possible to read the advisory at zeroscience.mk. This vulnerability is known as CVE-2016-20030 since 03/15/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 03/15/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2016-10815). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Incorrect behavior order
CWE: CWE-551
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/15/2026 Advisory disclosed
03/15/2026 +0 days CVE reserved
03/15/2026 +0 days VulDB entry created
03/15/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: ZSL-2016-5366
Researcher: Gjoko Krstic
Status: Not defined

CVE: CVE-2016-20030 (🔒)
GCVE (CVE): GCVE-0-2016-20030
GCVE (VulDB): GCVE-100-351127
EUVD: 🔒

Entryinfo

Created: 03/15/2026 15:11
Updated: 03/15/2026 16:43
Changes: 03/15/2026 15:11 (77), 03/15/2026 16:43 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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