CVE-2018-25097

Executive Summary

CVE-2018-25097 is a stored cross-site scripting (XSS) vulnerability in Acumos Design Studio versions up to and including 2.0.7. The vulnerability exists in an unknown function, allowing an attacker to inject malicious scripts that execute in the context of a victim's browser. The attack vector is remote, requiring user interaction. The vulnerability has a low CVSS score of 3.5 due to the need for user interaction and limited impact on confidentiality and integrity. The vendor has released a patch in version 2.0.8, and the fix is available via commit 0df8a5e8722188744973168648e4c74c69ce67fd. No public proof-of-concept or exploit code is available at this time.

Supply Chain & Package Security

Acumos Design Studio is a Java-based project hosted on GitHub. The vulnerability is not related to any specific package manager (NPM, PyPI, Go, Ruby). The patch is available in the project's source repository. Users should verify the integrity of the patched version by checking the commit hash and ensuring the build process is secure.

CVSS Breakdown & Threat Level

• CVSS Score: 3.5 (Low)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
• Attack Vector: Network (AV:N) – The vulnerability can be exploited remotely.
• Attack Complexity: Low (AC:L) – No special conditions are required.
• Privileges Required: None (PR:N) – No authentication needed.
• User Interaction: Required (UI:R) – The victim must click a link or visit a crafted page.
• Scope: Unchanged (S:U) – The vulnerable component and the impacted component are the same.
• Confidentiality Impact: None (C:N) – No data exposure.
• Integrity Impact: Low (I:L) – Limited modification of data.
• Availability Impact: None (A:N) – No denial of service.

Threat Level: Low. The vulnerability requires user interaction and has limited impact. However, in a context where sensitive data is displayed in the browser, it could be used for phishing or session hijacking.

Deep Dive & Mechanics

The vulnerability is a classic stored XSS (Cross-Site Scripting) in Acumos Design Studio. The application fails to properly sanitize user-supplied input before storing it and later rendering it in a web page. An attacker can inject malicious JavaScript code into a field (e.g., a project name, description, or comment). When an administrator or other user views the affected page, the script executes in their browser.

Attack Flow:

1. Attacker identifies an input field that is not sanitized (e.g., a project name).
2. Attacker submits a payload like <script>alert('XSS')</script>.
3. The payload is stored in the database.
4. When a victim views the page containing the stored data, the script executes.
5. The attacker can steal cookies, redirect the user, or perform actions on behalf of the victim.

The patch (commit 0df8a5e8722188744973168648e4c74c69ce67fd) likely adds output encoding or input validation to prevent script injection.

Vulnerable vs. Patched Code

The exact vulnerable code is not publicly disclosed, but based on the patch commit, the fix likely involves HTML encoding user input before rendering.

Vulnerable Code (Conceptual):

// Vulnerable: Directly outputs user input without encoding
out.println("<div>" + userInput + "</div>");

Patched Code (Conceptual):

// Patched: HTML-encodes user input
out.println("<div>" + StringEscapeUtils.escapeHtml4(userInput) + "</div>");

The patch ensures that any HTML or JavaScript in user input is escaped, preventing script execution.

Exploitation & Lab Setup

Red Team

Since no public exploit is available, a proof-of-concept can be developed:

1. Setup: Deploy Acumos Design Studio 2.0.7 in a lab environment (e.g., using Docker or a local installation).
2. Identify Input: Find a field that is stored and displayed (e.g., project name, description).
3. Craft Payload: Use a simple XSS payload:

   <script>alert('XSS')</script>
   

4. Inject: Submit the payload via the application's web interface.
5. Trigger: As an admin user, navigate to the page that displays the stored data.
6. Observe: The alert box appears, confirming XSS.

Advanced Payload:

<img src=x onerror=alert(document.cookie)>

Blue Team

1. Detection: Monitor for unusual input patterns (e.g., <script>, onerror=, javascript:).
2. Prevention: Implement Content Security Policy (CSP) headers to block inline scripts.
3. Response: If XSS is detected, isolate the affected user session, review logs for injected content, and remove the malicious data from the database.
4. Hardening: Apply the patch immediately and enforce input validation and output encoding.

Indicators of Compromise (IOCs)

• Network: HTTP requests containing <script> tags or event handlers (e.g., onerror, onload) in POST data.
• Logs: Application logs showing unusual characters in user input fields (e.g., <script>).
• File System: No file-based IOCs; the attack is purely web-based.
• Memory: No specific memory artifacts.

Example Log Entry:

POST /design-studio/project/create HTTP/1.1
Host: target.com
Content-Type: application/x-www-form-urlencoded
...
projectName=<script>alert('XSS')</script>

Detection Engineering

YARA Rule

rule detect_xss_payload_acumos {
    meta:
        description = "Detects XSS payloads targeting Acumos Design Studio CVE-2018-25097"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2018-25097"
    strings:
        $xss1 = /<script[^>]*>.*?<\/script>/is
        $xss2 = /on\w+\s*=\s*['\"].*?['\"]/is
        $xss3 = /javascript\s*:/is
    condition:
        any of them
}

Sigma Rule

title: XSS Payload in HTTP Request Body
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects potential XSS payloads in HTTP POST requests to Acumos Design Studio
author: Valters IT
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query|contains: '/design-studio/'
        cs-body|contains:
            - '<script'
            - 'onerror='
            - 'onload='
            - 'javascript:'
    condition: selection
falsepositives:
    - Legitimate use of HTML in descriptions (rare)
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2018-25097 XSS Payload in Acumos Design Studio"; flow:to_server,established; content:"POST"; http_method; content:"/design-studio/"; http_uri; pcre:"/<script[^>]*>.*?<\/script>/i"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Upgrade: Update Acumos Design Studio to version 2.0.8 or later.
2. Patch: If upgrade is not possible, apply the commit 0df8a5e8722188744973168648e4c74c69ce67fd manually.
3. Validate: After patching, test the application to ensure no regression.

Long-Term Mitigations:

• Implement a Web Application Firewall (WAF) with rules to block XSS payloads.
• Enforce Content Security Policy (CSP) headers to restrict script execution.
• Conduct regular security code reviews and penetration testing.
• Train developers on secure coding practices, especially input validation and output encoding.

Workaround (if patching is delayed):

• Disable the vulnerable functionality if possible.
• Restrict access to the application to trusted users only.

Valters IT