CVE-2023-28782
📋 TL;DR
CVE-2023-28782 is an unauthenticated PHP object injection vulnerability in Gravity Forms WordPress plugin that allows attackers to execute arbitrary code through deserialization of untrusted data. This affects all WordPress sites running Gravity Forms versions up to 2.7.3. Attackers can exploit this without authentication to gain control of vulnerable websites.
💻 Affected Systems
- Gravity Forms WordPress Plugin
📦 What is this software?
Gravity Forms by Gravityforms
⚠️ Risk & Real-World Impact
Worst Case
Complete server compromise leading to data theft, website defacement, malware distribution, and lateral movement within the hosting environment.
Likely Case
Remote code execution allowing attackers to create administrative users, install backdoors, steal sensitive data, and use the site for further attacks.
If Mitigated
Limited impact if proper web application firewalls and input validation are in place, though the core vulnerability remains exploitable.
🎯 Exploit Status
Exploits are publicly available and require minimal technical skill to execute against vulnerable installations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.7.4 and later
Vendor Advisory: https://www.gravityforms.com/gravity-forms-2-7-4-security-release/
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find Gravity Forms and click 'Update Now'. 4. Verify update to version 2.7.4 or later.
🔧 Temporary Workarounds
Web Application Firewall (WAF)
allImplement WAF rules to block deserialization attacks and PHP object injection attempts.
Disable Gravity Forms
linuxTemporarily disable the Gravity Forms plugin until patching is possible.
wp plugin deactivate gravityforms
🧯 If You Can't Patch
- Implement strict network segmentation to isolate WordPress installations from critical systems
- Enable comprehensive logging and monitoring for suspicious PHP object injection attempts
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin panel → Plugins → Gravity Forms version. If version is 2.7.3 or lower, system is vulnerable.Check Version:
wp plugin get gravityforms --field=versionVerify Fix Applied:
Verify Gravity Forms version is 2.7.4 or higher in WordPress admin panel.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to Gravity Forms endpoints
- PHP deserialization errors in web server logs
- Unexpected file creation in wp-content/uploads
Network Indicators:
- HTTP requests containing serialized PHP objects
- Traffic patterns matching known exploit payloads
SIEM Query:
source="web_server.logs" AND ("gravityforms" AND ("unserialize" OR "__destruct" OR "__wakeup"))🔗 References
- https://patchstack.com/database/vulnerability/gravityforms/wordpress-gravity-forms-plugin-2-7-3-unauthenticated-php-object-injection-vulnerability?_s_id=cve
- https://patchstack.com/database/vulnerability/gravityforms/wordpress-gravity-forms-plugin-2-7-3-unauthenticated-php-object-injection-vulnerability?_s_id=cve
