CVE-2021-3007
📋 TL;DR
CVE-2021-3007 is a PHP deserialization vulnerability in Laminas Project's laminas-http component (and Zend Framework) that allows remote code execution when attacker-controlled data is deserialized. The vulnerability exists in the __destruct method of the Stream class, which can be triggered to execute arbitrary code. This affects applications using vulnerable versions of laminas-http or Zend Framework that deserialize untrusted input.
💻 Affected Systems
- Laminas Project laminas-http
- Zend Framework
📦 What is this software?
Laminas Http by Getlaminas
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution with full system compromise, allowing attackers to execute arbitrary commands, install malware, or pivot to other systems.
Likely Case
Remote code execution leading to web server compromise, data theft, or botnet recruitment.
If Mitigated
Limited impact if proper input validation and deserialization controls prevent attacker-controlled data from reaching vulnerable code.
🎯 Exploit Status
Exploit requires attacker to control deserialized data. Public proof-of-concept exists and has been used in botnet campaigns like FreakOut.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: laminas-http 2.14.2 and later
Vendor Advisory: https://github.com/laminas/laminas-http/releases/tag/2.14.2
Restart Required: No
Instructions:
1. Update laminas-http to version 2.14.2 or later using composer: 'composer require laminas/laminas-http:^2.14.2' 2. For Zend Framework, migrate to Laminas Project components as Zend Framework is no longer supported.
🔧 Temporary Workarounds
Input Validation and Sanitization
allImplement strict input validation to prevent untrusted data from being deserialized
Disable Dangerous PHP Functions
linuxRestrict or disable PHP functions that could be used in exploitation
disable_functions = exec,passthru,shell_exec,system,proc_open,popen,curl_exec,curl_multi_exec,parse_ini_file,show_source
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block deserialization attacks
- Isolate affected systems in network segments with strict access controls
🔍 How to Verify
Check if Vulnerable:
Check composer.json or vendor/laminas/laminas-http/composer.json for version below 2.14.2Check Version:
composer show laminas/laminas-http | grep versionsVerify Fix Applied:
Verify laminas-http version is 2.14.2 or higher: 'composer show laminas/laminas-http'📡 Detection & Monitoring
Log Indicators:
- Unusual PHP process execution patterns
- Deserialization errors in application logs
- Suspicious POST/PUT requests with serialized data
Network Indicators:
- HTTP requests containing serialized PHP objects
- Outbound connections from web servers to unknown IPs
SIEM Query:
source="web_logs" AND ("__destruct" OR "unserialize" OR "phar://")🔗 References
- https://github.com/Ling-Yizhou/zendframework3-/blob/main/zend%20framework3%20%E5%8F%8D%E5%BA%8F%E5%88%97%E5%8C%96%20rce.md
- https://github.com/laminas/laminas-http/commits/2.15.x/src/Response/Stream.php
- https://github.com/laminas/laminas-http/pull/48
- https://github.com/laminas/laminas-http/releases/tag/2.14.2
- https://research.checkpoint.com/2021/freakout-leveraging-newest-vulnerabilities-for-creating-a-botnet/
- https://github.com/Ling-Yizhou/zendframework3-/blob/main/zend%20framework3%20%E5%8F%8D%E5%BA%8F%E5%88%97%E5%8C%96%20rce.md
- https://github.com/laminas/laminas-http/commits/2.15.x/src/Response/Stream.php
- https://github.com/laminas/laminas-http/pull/48
- https://github.com/laminas/laminas-http/releases/tag/2.14.2
- https://research.checkpoint.com/2021/freakout-leveraging-newest-vulnerabilities-for-creating-a-botnet/
