How severe is CVE-2021-44554?

CVE-2021-44554 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-44554 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-44554?

CVE-2021-44554 affects Cybelesoft Thinfinity Virtualui. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-44554?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-44554 published?

CVE-2021-44554 was published on 2021-12-20 and last updated on 2026-06-17.

CVE-2021-44554

CVE-2021-44554 is a medium-severity vulnerability in Cybelesoft Thinfinity Virtualui with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-203.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Cybelesoft Thinfinity Virtualui
Published: 2021-12-20
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-44554?: 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.
How severe is CVE-2021-44554?: CVE-2021-44554 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-44554 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-44554?: CVE-2021-44554 affects Cybelesoft Thinfinity Virtualui. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-44554?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-44554 published?: CVE-2021-44554 was published on 2021-12-20 and last updated on 2026-06-17.

References

https://github.com/cybelesoft/virtualui/issues/1

Affected products (1)

cpe:2.3:a:cybelesoft:thinfinity_virtualui:*:*:*:*:*:*:*:*

More vulnerabilities in Cybelesoft Thinfinity Virtualui

CVE-2021-45092 — Critical (CVSS 9.8): Thinfinity VirtualUI before 3.0 has functionality in /lab.html reachable by default that could allow IFRAME injection…
CVE-2021-46354 — High (CVSS 7.5): Thinfinity VirtualUI 2.1.28.0, 2.1.32.1 and 2.5.26.2, fixed in version 3.0 is affected by an information disclosure…
CVE-2019-16384 — Medium (CVSS 6.5): Cybele Thinfinity VirtualUI 2.5.17.2 allows ../ path traversal that can be used for data exfiltration. This enables…
CVE-2019-16385 — Medium (CVSS 6.1): Cybele Thinfinity VirtualUI 2.5.17.2 allows HTTP response splitting via the mimetype parameter within a PDF viewer…
CVE-2021-44848 — Medium (CVSS 5.3): In Cibele Thinfinity VirtualUI before 3.0, /changePassword returns different responses for invalid authentication…

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CVE-2024-25714 — Critical (CVSS 9.8): In Rhonabwy through 1.1.13, HMAC signature verification uses a strcmp function that is vulnerable to side-channel…
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Browse all CWE-203 (Observable Discrepancy) vulnerabilities →