CVE-2025-39495
📋 TL;DR
A PHP object injection vulnerability in the BoldThemes Avantage WordPress theme allows attackers to execute arbitrary code through deserialization of untrusted data. This affects all Avantage theme installations up to version 2.4.6. Attackers can exploit this to gain unauthorized access and control over affected WordPress sites.
💻 Affected Systems
- BoldThemes Avantage WordPress Theme
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete site compromise, data theft, malware deployment, and server takeover.
Likely Case
Unauthorized administrative access, backdoor installation, and data exfiltration from the WordPress site.
If Mitigated
Limited impact if proper input validation and security controls prevent exploitation attempts.
🎯 Exploit Status
Exploit details are publicly available. Attackers can craft malicious serialized objects to trigger the vulnerability.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.4.7 or later
Vendor Advisory: https://patchstack.com/database/wordpress/theme/avantage/vulnerability/wordpress-avantage-theme-2-4-6-php-object-injection-vulnerability?_s_id=cve
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Appearance > Themes. 3. Check for Avantage theme updates. 4. Update to version 2.4.7 or later. 5. Clear any caching plugins.
🔧 Temporary Workarounds
Disable Avantage Theme
allSwitch to a different WordPress theme until patched
wp theme activate twentytwentyfour
wp theme deactivate avantage
Web Application Firewall Rule
allBlock requests containing serialized PHP objects
ModSecurity rule: SecRule REQUEST_BODY "@rx (O:\d+:\"[^\"]+\":\d+:\{[^}]+\})" "id:1001,phase:2,deny,status:403,msg:'PHP Object Injection Attempt'"
WAF configuration to block serialized data patterns
🧯 If You Can't Patch
- Disable the Avantage theme immediately and switch to a secure alternative theme.
- Implement strict input validation and sanitization for all user-controlled data in WordPress.
🔍 How to Verify
Check if Vulnerable:
Check WordPress theme version: wp theme list --field=name,status,version | grep avantageCheck Version:
wp theme list --field=name,version | grep avantageVerify Fix Applied:
Confirm Avantage theme version is 2.4.7 or higher: wp theme list --field=name,version | grep avantage📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to theme files
- Serialized data patterns in request logs
- Unexpected PHP object instantiation in error logs
Network Indicators:
- HTTP requests containing serialized PHP objects (O: patterns)
- Unusual traffic to theme PHP files
SIEM Query:
source="web_logs" AND (uri="*avantage*" OR uri="*theme*php") AND (request_body="*O:\d+:*" OR request_body="*serialize*" OR request_body="*unserialize*")