CVE-2023-6620
📋 TL;DR
This SQL injection vulnerability in the POST SMTP Mailer WordPress plugin allows authenticated administrators to execute arbitrary SQL commands on the database. It affects WordPress sites using vulnerable versions of the plugin, potentially compromising the entire site's data integrity and confidentiality.
💻 Affected Systems
- POST SMTP Mailer WordPress Plugin
📦 What is this software?
Post Smtp by Wpexperts
⚠️ Risk & Real-World Impact
Worst Case
Complete database compromise leading to data theft, data manipulation, privilege escalation, or full site takeover via arbitrary code execution.
Likely Case
Unauthorized database access allowing attackers to steal sensitive information like user credentials, emails, or configuration data.
If Mitigated
Limited impact due to proper access controls and monitoring, with only authorized administrators able to trigger the vulnerability.
🎯 Exploit Status
Exploitation requires admin-level access. SQL injection is a well-understood attack vector with many available tools.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.8.7
Vendor Advisory: https://wpscan.com/vulnerability/ab5c42ca-ee7d-4344-bd88-0d727ed3d9c4
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins > Installed Plugins. 3. Find POST SMTP Mailer. 4. Click 'Update Now' if available. 5. Alternatively, download version 2.8.7+ from WordPress repository and manually update.
🔧 Temporary Workarounds
Temporary Plugin Deactivation
allDisable the vulnerable plugin until patching is possible
wp plugin deactivate post-smtp
Restrict Admin Access
allTemporarily limit administrative access to trusted IP addresses only
🧯 If You Can't Patch
- Implement strict access controls and monitoring for admin accounts
- Deploy web application firewall with SQL injection protection rules
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin panel > Plugins > POST SMTP Mailer version numberCheck Version:
wp plugin list --name=post-smtp --field=versionVerify Fix Applied:
Confirm plugin version is 2.8.7 or higher in WordPress admin📡 Detection & Monitoring
Log Indicators:
- Unusual SQL queries in WordPress or database logs
- Multiple failed login attempts followed by admin access
- Unexpected database schema changes
Network Indicators:
- Suspicious POST requests to wp-admin containing SQL syntax
- Unusual database connection patterns from web server
SIEM Query:
source="wordpress.log" AND ("sql" OR "union" OR "select" OR "insert" OR "update" OR "delete") AND "post-smtp"