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Vulnerability record · CVE-2021-44554 · published 20 December 2021

CVE-2021-44554: Cybelesoft thinfinity virtualui observable discrepancy vulnerability

Cybelesoft · Thinfinity Virtualui

Thinfinity VirtualUI before 3.0 allows a malicious actor to enumerate users registered in the OS (Windows) through the /changePassword URI. By accessing the vector, an attacker can determine if a username exists thanks to the message returned; it can be presented in different languages according to the configuration of VirtualUI. Common users are administrator, admin, guest and krgtbt.

5.3 CVSS 3.1 Medium EPSS 1.0% · top 37.7% CWE-203 · Observable discrepancy
5.3CVSS 3.1 base score, v2 5.0
1.0%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

Thinfinity VirtualUI before 3.0 allows a malicious actor to enumerate users registered in the OS (Windows) through the /changePassword URI. By accessing the vector, an attacker can determine if a username exists thanks to the message returned; it can be presented in different languages according to the configuration of VirtualUI. Common users are administrator, admin, guest and krgtbt.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/cybelesoft/virtualui/issues/1 ExploitIssue TrackingThird Party Advisory
https://github.com/cybelesoft/virtualui/issues/1 ExploitIssue TrackingThird Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-44554), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.