CVE-2021-47890CWE-428

LogonExpert 8.1 - 'LogonExpertSvc' Unquoted Service Path

High · published January 23, 2026

CVSS v4.0
8.5
EPSS
0%
Percentile
3.3
In the wild
Unconfirmed
What it is

⚡ An unquoted service path in LogonExpert 8.1 is a golden ticket for attackers! 🏴‍☠️ They can sneak malicious executables into the service startup process, potentially gaining elevated system access with a simple trick. This vulnerability is like a delivery driver bringing a package to a building that has a poorly labelled delivery entrance. Just because the door says 'Employees Only' doesn’t mean anyone can’t sneak in with a convincing delivery slip! 📦 If an attacker successfully exploits this flaw, they could run arbitrary code with LocalSystem privileges—essentially gaining the keys to the kingdom. They could manipulate system settings, compromise sensitive data, or even install additional malware, leading to severe consequences for your organization.

Put simply

This vulnerability is like a delivery driver bringing a package to a building that has a poorly labelled delivery entrance. Just because the door says 'Employees Only' doesn’t mean anyone can’t sneak in with a convincing delivery slip! 📦 The unquoted service path vulnerability in LogonExpert allows attackers to place executables in directories leading to the service startup, which runs with high-level privileges, enabling unauthorized code execution.

What to do

If an attacker successfully exploits this flaw, they could run arbitrary code with LocalSystem privileges—essentially gaining the keys to the kingdom. They could manipulate system settings, compromise sensitive data, or even install additional malware, leading to severe consequences for your organization. To safeguard against this vulnerability, ensure you update LogonExpert to the latest version that addresses this flaw. Additionally, verify that all service paths are quoted correctly and follow up with a review of your service configurations for any other potential issues. You've got this! With these steps, your system will be well-protected against this pesky vulnerability. 🛡️

The record
Technical detail
CVSS v4.0
8.5 · HIGH
Vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.00143 · 3.3th percentile
Weakness
CWE-428 · Unquoted Search Path or Element
Published
2026-01-23T16:47Z
EPSS history
Timeline
  • 23 JAN 16:47Z
    LogonExpert 8.1 - 'LogonExpertSvc' Unquoted Service Path
    cvelistv5