CVE-2025-2690
📋 TL;DR
This critical vulnerability in Yii2 PHP framework allows remote attackers to execute arbitrary code through insecure deserialization in the phpunit mock object generator. It affects all Yii2 applications using phpunit testing components up to version 2.0.39. Attackers can exploit this to gain control of affected web servers.
💻 Affected Systems
- yiisoft Yii2
📦 What is this software?
Yii by Yiiframework
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, and lateral movement within the network.
Likely Case
Remote code execution allowing attackers to deploy malware, create backdoors, or exfiltrate sensitive data from the web server.
If Mitigated
Limited impact if proper input validation and deserialization controls are in place, though exploitation may still be possible.
🎯 Exploit Status
Public exploit details available; deserialization vulnerabilities are commonly weaponized in automated attacks.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.0.40 or later
Vendor Advisory: https://github.com/yiisoft/yii2/security/advisories
Restart Required: No
Instructions:
1. Update Yii2 to version 2.0.40 or later via composer: 'composer require yiisoft/yii2:^2.0.40' 2. Run 'composer update' 3. Verify the update completed successfully.
🔧 Temporary Workarounds
Disable phpunit in production
allRemove or disable phpunit testing components from production environments
composer remove --dev phpunit/phpunit
Remove phpunit directories from production deployment
Input validation filter
allImplement strict input validation to block deserialization attempts
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block deserialization payloads
- Restrict network access to affected systems and implement strict network segmentation
🔍 How to Verify
Check if Vulnerable:
Check composer.json or vendor/yiisoft/yii2/BaseYii.php for version number less than 2.0.40Check Version:
php -r "echo \Yii::getVersion();" or check composer.lock for yiisoft/yii2 versionVerify Fix Applied:
Verify version is 2.0.40 or higher and test that deserialization attempts are properly rejected📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to phpunit endpoints
- Deserialization errors in PHP logs
- Unexpected process execution from web user
Network Indicators:
- HTTP requests containing serialized PHP objects
- Outbound connections from web server to unknown destinations
SIEM Query:
source="web_logs" AND (uri="*phpunit*" OR uri="*MockClass*" OR message="*unserialize*" OR message="*__destruct*")