Описание
systeminformation has a Command Injection vulnerability in fsSize() function on Windows
Summary
The fsSize() function in systeminformation is vulnerable to OS Command Injection (CWE-78) on Windows systems. The optional drive parameter is directly concatenated into a PowerShell command without sanitization, allowing arbitrary command execution when user-controlled input reaches this function.
Affected Platforms: Windows only
CVSS Breakdown:
- Attack Vector (AV:N): Network - if used in a web application/API
- Attack Complexity (AC:H): High - requires application to pass user input to
fsSize() - Privileges Required (PR:N): None - no authentication required at library level
- User Interaction (UI:N): None
- Scope (S:U): Unchanged - executes within Node.js process context
- Confidentiality/Integrity/Availability (C:H/I:H/A:H): High impact if exploited
Note: The actual exploitability depends on how applications use this function. If an application does not pass user-controlled input to
fsSize(), it is not vulnerable.
Details
Vulnerable Code Location
File: lib/filesystem.js, Line 197
The drive parameter is concatenated directly into the PowerShell command string without any sanitization.
Why This Is a Vulnerability
This is inconsistent with the security pattern used elsewhere in the codebase. Other functions properly sanitize user input using util.sanitizeShellString():
| File | Line | Function | Sanitization |
|---|---|---|---|
lib/processes.js | 141 | services() | ✅ util.sanitizeShellString(srv) |
lib/processes.js | 1006 | processLoad() | ✅ util.sanitizeShellString(proc) |
lib/network.js | 1253 | networkStats() | ✅ util.sanitizeShellString(iface) |
lib/docker.js | 472 | dockerContainerStats() | ✅ util.sanitizeShellString(containerIDs, true) |
lib/filesystem.js | 197 | fsSize() | ❌ No sanitization |
The sanitizeShellString() function (defined at lib/util.js:731) removes dangerous characters like ;, &, |, $, `, #, etc., which would prevent command injection.
PoC
Attack Scenario
An application exposes disk information via an API and passes user input to si.fsSize():
Exploitation
Normal Request:
Malicious Request (Command Injection):
Command Construction Demonstration
The following demonstrates how commands are constructed with malicious input:
Normal usage:
With injection payload C:; whoami #:
PowerShell will execute:
Get-WmiObject Win32_logicaldisk | ... | where -property Caption -eq C:(original command)whoami(injected command)- Everything after
#is commented out
PoC Script
PoC Output
As shown, the attacker's commands are injected directly into the PowerShell command string.
Impact
Who Is Affected?
- Applications running
systeminformationon Windows that pass user-controlled input tofsSize(drive) - Web applications, APIs, or CLI tools that accept drive letters from users
- Monitoring dashboards that allow users to specify which drives to query
Potential Attack Scenarios
- Remote Code Execution (RCE) - Execute arbitrary commands with Node.js process privileges
- Data Exfiltration - Read sensitive files and exfiltrate data
- Privilege Escalation - If Node.js runs with elevated privileges
- Lateral Movement - Use the compromised system to attack internal network
- Ransomware Deployment - Download and execute malicious payloads
Recommended Fix
Apply util.sanitizeShellString() to the drive parameter, consistent with other functions in the codebase:
The true parameter enables strict mode which removes additional characters like spaces and parentheses.
systeminformation thanks developers working on the project. The Systeminformation Project hopes this report helps improve the its security. Please systeminformation know if any additional information or clarification is needed.
Пакеты
systeminformation
< 5.27.14
5.27.14
Связанные уязвимости
systeminformation is a System and OS information library for node.js. In versions prior to 5.27.14, the `fsSize()` function in systeminformation is vulnerable to OS command injection on Windows systems. The optional `drive` parameter is directly concatenated into a PowerShell command without sanitization, allowing arbitrary command execution when user-controlled input reaches this function. The actual exploitability depends on how applications use this function. If an application does not pass user-controlled input to `fsSize()`, it is not vulnerable. Version 5.27.14 contains a patch.