CVE-2020-19229
📋 TL;DR
CVE-2020-19229 is a critical vulnerability in Jeesite 1.2.7 that uses a vulnerable version of Apache Shiro (1.2.3). This allows attackers to exploit a Java deserialization flaw via the rememberMe parameter to execute arbitrary commands on affected systems. Organizations running Jeesite 1.2.7 with default configurations are at risk.
💻 Affected Systems
- Jeesite
📦 What is this software?
Jeesite by Jeesite
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with remote code execution leading to data theft, ransomware deployment, or complete system takeover.
Likely Case
Unauthenticated attackers gaining shell access to the server, installing backdoors, and pivoting to internal networks.
If Mitigated
Attackers blocked at perimeter with proper input validation and network segmentation limiting lateral movement.
🎯 Exploit Status
Exploit tools for CVE-2016-4437 (the underlying Shiro vulnerability) are widely available and can be adapted for Jeesite.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Update Apache Shiro to version 1.2.5 or later
Vendor Advisory: https://github.com/thinkgem/jeesite/issues/490
Restart Required: Yes
Instructions:
1. Stop Jeesite service. 2. Update Apache Shiro dependency to version 1.2.5+. 3. Update Jeesite if newer versions exist. 4. Restart Jeesite service. 5. Verify fix by testing exploit attempts.
🔧 Temporary Workarounds
Disable rememberMe functionality
allTemporarily disable Shiro's rememberMe feature to block the attack vector
Edit shiro.ini or equivalent config file and set shiro.rememberMe.enabled = false
WAF rule blocking
allImplement web application firewall rules to block rememberMe parameter exploitation
Add WAF rule: Block requests containing malicious rememberMe cookie patterns
🧯 If You Can't Patch
- Network segmentation: Isolate Jeesite servers from critical systems and internet
- Strict input validation: Filter rememberMe parameter at application or proxy level
🔍 How to Verify
Check if Vulnerable:
Check Jeesite version in web interface or configuration files, and verify Apache Shiro version in dependencies (typically in pom.xml or lib directory).Check Version:
Check Jeesite version: grep -r 'version' web.xml or similar config files. Check Shiro version: find . -name '*.jar' | grep shiroVerify Fix Applied:
Test with known exploit payloads for CVE-2016-4437 against the rememberMe parameter - successful exploitation should fail after patching.📡 Detection & Monitoring
Log Indicators:
- Unusual rememberMe parameter values in access logs
- Java deserialization errors in application logs
- Unexpected process execution from web server user
Network Indicators:
- HTTP requests with unusually long rememberMe cookies
- Outbound connections from web server to unknown IPs
SIEM Query:
source="web_access_logs" AND rememberMe AND (length(rememberMe) > 100 OR rememberMe CONTAINS "rO0AB")