CVE-2021-47890

LogonExpert 8.1 contains an unquoted service path vulnerability in the LogonExpertSvc service running with LocalSystem privileges. Attackers can exploit the unquoted path to place malicious executables in intermediate directories, potentially gaining elevated system access during service startup.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://download.logonexpert.com/LogonExpertSetup64.msi
https://www.exploit-db.com/exploits/49586
https://www.softros.com/
https://www.vulncheck.com/advisories/logonexpert-logonexpertsvc-unquoted-service-path

Configurations

No configuration.

History

23 Jan 2026, 17:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-23 17:15

Updated : 2026-01-26 15:03

NVD link : CVE-2021-47890

Mitre link : CVE-2021-47890

CVE.ORG link : CVE-2021-47890

JSON object : View

Products Affected

No product.

CWE

CWE-428

Unquoted Search Path or Element

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