GHSA-wphj-fx3q-84ch systeminformation has a Command Injection vulnerability in fsSize() function on Windows
SummaryThe `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.DetailsVulnerable 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 VulnerabilityThis 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.PoCAttack ScenarioAn application exposes disk information via an API and passes user input to `si.fsSize()`:Exploitation**Normal Request:****Malicious Request (Command Injection):**Command Construction DemonstrationThe 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 outPoC ScriptPoC OutputAs shown, the attacker's commands are injected directly into the PowerShell command string.ImpactWho 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 usersMonitoring dashboards that allow users to specify which drives to queryPotential 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 payloadsRecommended FixApply `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.
CVSS v3.1 score: 8.1