CVE-2025-65113
📋 TL;DR
ClipBucket v5 has an authorization bypass vulnerability in its AJAX flagging system that allows unauthenticated users to flag any content (users, videos, photos, collections). This affects all ClipBucket v5 installations prior to version 5.5.2 - #164, potentially enabling mass flagging attacks and moderation system abuse.
💻 Affected Systems
- ClipBucket v5
📦 What is this software?
Clipbucket by Oxygenz
⚠️ Risk & Real-World Impact
Worst Case
Mass flagging attacks could overwhelm moderation systems, cause content takedowns, disrupt platform operations, and damage user trust through coordinated abuse campaigns.
Likely Case
Unauthenticated users flagging legitimate content, creating moderation workload spikes, and potentially causing temporary content removal until manual review.
If Mitigated
With proper monitoring and rapid response, impact is limited to increased moderation workload and minor user disruption.
🎯 Exploit Status
The vulnerability is simple to exploit via AJAX requests without authentication; automated scripts could easily weaponize this for mass flagging attacks.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 5.5.2 - #164
Vendor Advisory: https://github.com/MacWarrior/clipbucket-v5/security/advisories/GHSA-9f8v-vph8-pq6q
Restart Required: No
Instructions:
1. Backup your ClipBucket installation and database. 2. Download version 5.5.2 - #164 from the official repository. 3. Replace affected files with patched versions. 4. Verify the fix by testing flagging functionality.
🔧 Temporary Workarounds
Temporary AJAX Flagging Disable
allDisable the vulnerable AJAX flagging endpoint to prevent exploitation while planning upgrade.
# Modify your web server configuration to block access to the flagging endpoint
# Example for Apache: RewriteRule ^/ajax/flag_content - [F]
# Example for Nginx: location ~ ^/ajax/flag_content { return 403; }
🧯 If You Can't Patch
- Implement rate limiting on flagging endpoints to prevent mass attacks
- Enable detailed logging for flagging actions and monitor for suspicious patterns
🔍 How to Verify
Check if Vulnerable:
Attempt to flag content via AJAX without authentication; if successful, the system is vulnerable.Check Version:
Check the ClipBucket version in admin panel or review the software version files.Verify Fix Applied:
After patching, attempt unauthenticated flagging; it should fail with proper authorization error.📡 Detection & Monitoring
Log Indicators:
- Multiple flagging requests from same IP without authentication
- Unusual spike in flagging activity
- Flagging requests with missing or invalid session tokens
Network Indicators:
- HTTP POST requests to /ajax/flag_content endpoint without authentication headers
- High volume of flagging requests from single sources
SIEM Query:
source="web_logs" AND (uri_path="/ajax/flag_content" OR uri_path LIKE "%/ajax/flag_content%") AND NOT (user_agent CONTAINS "authenticated" OR cookie CONTAINS "session") | stats count by src_ip