CVE-2021-28151

What is this vulnerability?

CVE-2021-28151 is categorized as a high OS Command Injection flaw with a CVSS base score of 8.8. Based on our vulnerability intelligence, this issue occurs when the application fails to securely handle untrusted data boundaries.

Hongdian H8922 3.0.5 devices allow OS command injection via shell metacharacters into the ip-address (aka Destination) field to the tools.cgi ping command, which is accessible with the username guest and password guest.

This architectural defect enables adversaries to bypass intended security controls, directly manipulating the application's execution state or data layer. Immediate strategic intervention is required.

Risk Assessment

Impact on Systems

✅ Data Exfiltration: Attackers can extract sensitive data from backend databases, configuration files, or internal services.

✅ Authentication Bypass: Exploiting this flaw may allow unauthorized access to protected resources and administrative interfaces.

✅ Lateral Movement: Once initial access is gained, attackers can pivot to internal systems and escalate privileges.

How to Fix and Mitigate CVE-2021-28151

1. Apply Vendor Patches: Upgrade affected components to their latest, non-vulnerable versions immediately.
2. Implement Input Validation: Ensure all user-supplied data is validated, sanitized, and type-checked before processing.
3. Deploy Runtime Protection: Use Precogs continuous monitoring to detect exploitation attempts in real time.
4. Audit Dependencies: Review and update all third-party libraries and transitive dependencies.

Defending with Precogs AI

Hongdian H8922 routers contain a hardcoded credential vulnerability. Attackers connect via telnet or SSH using default engineering credentials to gain full administrative control over the industrial router. Precogs PII & Secrets Scanner automatically identifies hardcoded credentials in firmware.

Use Precogs to continuously scan your codebase, binaries, APIs, and infrastructure for this vulnerability class and related attack patterns. Our AI-powered detection engine combines static analysis with threat intelligence to identify exploitable weaknesses before attackers do.

Start scanning with Precogs →

Vulnerability Code Signature

Attack Data Flow

Vulnerable Code Pattern

// ❌ VULNERABLE: OS command injection
const { exec } = require('child_process');
function pingHost(host) {
  // Taint sink: unvalidated host string executed in shell
  exec('ping -c 4 ' + host, (error, stdout, stderr) => {
    console.log(stdout);
  });
}

Secure Code Pattern

// ✅ SECURE: ExecFile with parameter arrays
const { execFile } = require('child_process');
function pingHost(host) {
  // Sanitized execution: arguments passed safely, bypassing shell interpolation
  execFile('ping', ['-c', '4', host], (error, stdout, stderr) => {
    console.log(stdout);
  });
}

How Precogs Detects This

Precogs AI Analysis Engine natively intercepts unsafe OS command execution sinks, ensuring all arguments are properly separated from the execution context.\n