CVE-2026-35183: Brave CMS Auth Bypass Vulnerability

CVE-2026-35183 Overview

An Insecure Direct Object Reference (IDOR) vulnerability has been identified in Brave CMS, an open-source content management system. The vulnerability exists in the article image deletion feature, specifically within the deleteImage method located in app/Http/Controllers/Dashboard/ArticleController.php. The endpoint accepts a filename from the URL but fails to verify ownership, allowing an authenticated user with edit permissions to delete images attached to articles owned by other users.

Critical Impact

Authenticated users can bypass authorization controls to delete images belonging to other users' articles, potentially disrupting content integrity and causing data loss across the CMS platform.

Affected Products

• Brave CMS versions prior to 2.0.6
• BraveCMS-2.0 installations with article editing functionality enabled
• Any deployment allowing multiple authenticated users with edit permissions

Discovery Timeline

• 2026-04-06 - CVE-2026-35183 published to NVD
• 2026-04-07 - Last updated in NVD database

Technical Details for CVE-2026-35183

Vulnerability Analysis

This vulnerability is classified under CWE-639 (Authorization Bypass Through User-Controlled Key), representing a classic Insecure Direct Object Reference (IDOR) flaw. The vulnerability allows authenticated users with standard edit permissions to access and manipulate resources belonging to other users without proper authorization verification.

The flaw occurs because the deleteImage method in the ArticleController.php file processes image deletion requests based solely on the filename provided in the URL parameter. The application fails to validate whether the requesting user has ownership or appropriate permissions over the specified image resource before processing the deletion operation.

Root Cause

The root cause of this vulnerability lies in missing authorization checks within the deleteImage method. When processing image deletion requests, the application:

1. Accepts the filename directly from the URL without validation
2. Does not verify that the authenticated user owns the article associated with the image
3. Proceeds with deletion based solely on the existence of the file

This represents a failure to implement proper object-level authorization controls, allowing any authenticated user with edit permissions to reference and delete images from any article in the system.

Attack Vector

The attack leverages network access to the vulnerable endpoint. An attacker with a valid authenticated session and edit permissions can enumerate or guess filenames of images attached to other users' articles. By crafting requests to the vulnerable endpoint with these filenames, the attacker can delete images without being the rightful owner.

The attack flow involves:

1. Authenticating to the Brave CMS dashboard with a user account that has edit permissions
2. Identifying or enumerating image filenames associated with other users' articles
3. Sending deletion requests to the vulnerable endpoint with the target filenames
4. Successfully removing images from articles the attacker does not own

The vulnerability is exploitable through direct HTTP requests to the deleteImage endpoint in the ArticleController. The absence of ownership verification allows the deletion to proceed regardless of which user originally uploaded the image. For detailed technical information, refer to the GitHub Security Advisory.

Detection Methods for CVE-2026-35183

Indicators of Compromise

• Unexpected image deletion events in article content without corresponding user actions from the article owner
• Access logs showing deletion requests to the ArticleControllerdeleteImage endpoint from users who do not own the targeted articles
• Reports from users about missing images in their articles that they did not remove
• Audit trail entries showing cross-user image deletion patterns

Detection Strategies

• Implement logging and monitoring on the deleteImage endpoint to track all deletion requests and correlate them with article ownership
• Deploy Web Application Firewall (WAF) rules to detect anomalous patterns of image deletion requests from single sessions
• Enable application-level audit logging to capture user ID, article ID, and image filename for all deletion operations
• Monitor for bulk or rapid succession deletion requests that may indicate automated exploitation

Monitoring Recommendations

• Set up alerts for image deletion operations where the requesting user differs from the article owner
• Review access logs regularly for patterns of unauthorized resource access attempts
• Implement rate limiting on the image deletion endpoint to slow potential enumeration attacks
• Configure centralized logging to correlate authentication events with resource manipulation activities

How to Mitigate CVE-2026-35183

Immediate Actions Required

• Upgrade Brave CMS to version 2.0.6 or later immediately to address this vulnerability
• Review audit logs to identify any potential exploitation that may have occurred before patching
• Assess the scope of any unauthorized image deletions and restore affected content from backups if necessary
• Temporarily restrict edit permissions to trusted users until the patch is applied

Patch Information

The vulnerability has been fixed in Brave CMS version 2.0.6. Users should upgrade to this version or later to remediate the IDOR vulnerability. The patch implements proper ownership verification in the deleteImage method to ensure users can only delete images attached to their own articles.

For additional details on the security fix, refer to the GitHub Security Advisory.

Workarounds

• Implement additional authorization middleware to validate article ownership before processing image deletion requests
• Restrict the deleteImage endpoint access to administrator-level users only until patching is complete
• Deploy WAF rules to block unauthorized deletion requests based on session user and resource ownership validation
• Disable the image deletion feature temporarily if it is not critical to operations

# Configuration example
# Restrict access to the ArticleController deleteImage endpoint via web server configuration
# Example for Apache (.htaccess):
<Location "/dashboard/article/deleteImage">
    Require user admin
</Location>

# Example for Nginx:
location ~* /dashboard/article/deleteImage {
    auth_basic "Admin Only";
    auth_basic_user_file /etc/nginx/.htpasswd;
}