CVE-2021-47850: Mini Mouse Path Traversal Vulnerability

CVE-2021-47850 Overview

CVE-2021-47850 is a path traversal vulnerability (CWE-22) affecting Mini Mouse version 9.2.0, a remote control application. This vulnerability allows remote attackers to access arbitrary system files and directories through crafted HTTP requests. Attackers can retrieve sensitive files like win.ini and list contents of system directories such as C:\Users\Public by manipulating file and path parameters in requests to the application's web server component.

Critical Impact

Remote attackers can read arbitrary files from the target system without authentication, potentially exposing sensitive configuration files, credentials, and user data.

Affected Products

• Mini Mouse 9.2.0

Discovery Timeline

• 2026-01-21 - CVE CVE-2021-47850 published to NVD
• 2026-01-21 - Last updated in NVD database

Technical Details for CVE-2021-47850

Vulnerability Analysis

Mini Mouse 9.2.0 contains a path traversal vulnerability in its HTTP server component that fails to properly sanitize user-supplied input in file path parameters. When the application receives HTTP requests containing specially crafted path sequences, it does not adequately validate or restrict access to files outside the intended directory scope.

The vulnerability stems from insufficient input validation on file and path parameters within HTTP requests. Attackers can leverage directory traversal sequences (such as ../ or URL-encoded variants) to escape the application's web root directory and access arbitrary locations on the file system.

Root Cause

The root cause is improper input validation (CWE-22: Improper Limitation of a Pathname to a Restricted Directory). The Mini Mouse application does not properly sanitize path parameters in incoming HTTP requests before processing file operations. This allows attackers to use relative path sequences to traverse outside the intended directory structure and access sensitive system files.

Attack Vector

The attack is network-based and requires no authentication or user interaction. An attacker with network access to the Mini Mouse application can send specially crafted HTTP requests containing directory traversal sequences in file or path parameters. By manipulating these parameters, the attacker can:

1. Read arbitrary files from the system (e.g., win.ini, configuration files, credentials)
2. List contents of system directories (e.g., C:\Users\Public)
3. Potentially enumerate the file system structure for further reconnaissance

The vulnerability is documented in Exploit-DB #49744, which provides technical details about the exploitation method. Additional information is available in the VulnCheck Advisory on Mini Mouse.

Detection Methods for CVE-2021-47850

Indicators of Compromise

• HTTP requests containing directory traversal patterns such as ../, ..\, %2e%2e%2f, or %2e%2e/ targeting the Mini Mouse application
• Requests attempting to access known system files like win.ini, boot.ini, hosts, or files in C:\Windows\System32
• Unusual file read operations from the Mini Mouse process targeting directories outside its installation path
• Network traffic to the Mini Mouse web server port containing encoded path traversal sequences

Detection Strategies

• Deploy web application firewall (WAF) rules to detect and block HTTP requests containing path traversal patterns
• Monitor Mini Mouse application logs for requests with suspicious file path parameters
• Use endpoint detection and response (EDR) solutions to alert on file access attempts from the Mini Mouse process to sensitive system locations
• Implement network intrusion detection rules to identify path traversal attempts in HTTP traffic

Monitoring Recommendations

• Enable verbose logging on the Mini Mouse application if available and monitor for anomalous file access patterns
• Set up alerts for any process named Mini Mouse or its executable attempting to read files outside its application directory
• Monitor network traffic for connections to the Mini Mouse service port, particularly from external or untrusted networks
• Review endpoint telemetry for file read operations targeting sensitive Windows configuration files

How to Mitigate CVE-2021-47850

Immediate Actions Required

• Disable or uninstall Mini Mouse 9.2.0 if not critically needed until a patched version is available
• Restrict network access to the Mini Mouse application using firewall rules to allow connections only from trusted hosts
• Implement network segmentation to isolate systems running Mini Mouse from sensitive network resources
• Deploy web application firewall rules to block requests containing path traversal sequences

Patch Information

No vendor patch information is currently available in the CVE data. Users should monitor the Apple App Store listing and the VulnCheck Advisory for updates regarding a security fix. Consider migrating to alternative remote control solutions that have active security support.

Workarounds

• Restrict Mini Mouse to listen only on localhost or trusted network interfaces if configuration options allow
• Use host-based firewall rules to limit incoming connections to the Mini Mouse application port
• Run Mini Mouse with a low-privileged user account to minimize the impact of file disclosure
• Consider using a reverse proxy in front of Mini Mouse with path filtering enabled to block traversal attempts

# Example Windows Firewall rule to restrict Mini Mouse access
netsh advfirewall firewall add rule name="Block Mini Mouse External" dir=in action=block protocol=tcp localport=<MINI_MOUSE_PORT> remoteip=any
netsh advfirewall firewall add rule name="Allow Mini Mouse Localhost" dir=in action=allow protocol=tcp localport=<MINI_MOUSE_PORT> remoteip=127.0.0.1