CVE-2025-59413
📋 TL;DR
CubeCart versions before 6.5.11 contain a logic flaw in the newsletter subscription endpoint that allows attackers to unsubscribe any user without consent. By manipulating the force_unsubscribe parameter in POST requests, attackers can forcibly remove valid subscribers' email addresses. This affects all CubeCart installations running vulnerable versions.
💻 Affected Systems
- CubeCart
📦 What is this software?
Cubecart by Cubecart
⚠️ Risk & Real-World Impact
Worst Case
Mass unsubscription of legitimate users from critical business communications, potentially disrupting customer relationships and violating privacy regulations.
Likely Case
Targeted unsubscription of specific users from newsletters and marketing communications, causing communication breakdowns and potential revenue loss.
If Mitigated
Limited impact with proper access controls and monitoring, though the vulnerability still exists in the codebase.
🎯 Exploit Status
Exploitation requires understanding of the API endpoint and ability to craft POST requests with the force_unsubscribe parameter.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 6.5.11
Vendor Advisory: https://github.com/cubecart/v6/security/advisories/GHSA-869v-gjv8-9m7f
Restart Required: No
Instructions:
1. Backup your CubeCart installation and database. 2. Download CubeCart 6.5.11 or newer from the official repository. 3. Replace all files with the new version, preserving configuration files. 4. Verify the installation works correctly.
🔧 Temporary Workarounds
Disable Newsletter Endpoint
allTemporarily disable the vulnerable newsletter subscription endpoint to prevent exploitation.
Modify .htaccess to block access to /index.php?_a=newsletter or equivalent endpoint
Input Validation Filter
allAdd server-side validation to reject requests with force_unsubscribe parameter set to 1.
Add validation in newsletter controller to check and reject force_unsubscribe=1 requests
🧯 If You Can't Patch
- Implement WAF rules to block requests containing force_unsubscribe=1 parameter
- Monitor newsletter subscription logs for unusual unsubscription patterns
🔍 How to Verify
Check if Vulnerable:
Check if CubeCart version is below 6.5.11 in admin panel or by examining version files.Check Version:
Check includes/global.inc.php for version number or view admin dashboardVerify Fix Applied:
After patching, test newsletter functionality and verify version shows 6.5.11 or higher.📡 Detection & Monitoring
Log Indicators:
- POST requests to newsletter endpoint with force_unsubscribe=1 parameter
- Unusual spike in newsletter unsubscriptions
Network Indicators:
- HTTP POST requests containing force_unsubscribe parameter
SIEM Query:
source="web_logs" AND uri_path="*newsletter*" AND post_params="*force_unsubscribe=1*"🔗 References
- https://github.com/cubecart/v6/commit/7fd1cd04f5d5c3ce1d7980327464f0ff6551de79
- https://github.com/cubecart/v6/commit/db965fcfa260c4f17eb16f8c5494e5af4a8ac271
- https://github.com/cubecart/v6/commit/dbc58cf1f7a6291f7add5893b56bff7920a29128
- https://github.com/cubecart/v6/security/advisories/GHSA-869v-gjv8-9m7f
- https://github.com/cubecart/v6/security/advisories/GHSA-869v-gjv8-9m7f
