CVE-2024-22088
📋 TL;DR
CVE-2024-22088 is a critical use-after-free vulnerability in Lotos WebServer that allows remote attackers to execute arbitrary code or cause denial of service by sending specially crafted long URIs. This affects all deployments running Lotos WebServer version 0.1.1 and earlier. Attackers can exploit this without authentication to potentially gain full control of affected systems.
💻 Affected Systems
- Lotos WebServer
📦 What is this software?
Lotos Webserver by Chendotjs
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, and persistent backdoor installation
Likely Case
Denial of service causing web server crashes and service disruption
If Mitigated
Limited to denial of service if memory protections are enabled
🎯 Exploit Status
Proof of concept available in GitHub issue; exploitation requires sending a long URI to trigger the use-after-free condition
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version after commit 3eb36cc
Vendor Advisory: https://github.com/chendotjs/lotos/issues/7
Restart Required: Yes
Instructions:
1. Stop Lotos WebServer service. 2. Update to latest version from GitHub repository. 3. Restart the web server service.
🔧 Temporary Workarounds
URI Length Restriction
allConfigure web server or reverse proxy to reject URIs longer than a safe threshold
# For nginx: client_max_body_size 1k;
# For Apache: LimitRequestLine 1024
Network Segmentation
linuxRestrict access to Lotos WebServer to trusted networks only
# iptables example: iptables -A INPUT -p tcp --dport [PORT] -s [TRUSTED_NET] -j ACCEPT
🧯 If You Can't Patch
- Deploy WAF with rules to block long URI requests
- Place behind reverse proxy with request size limits and input validation
🔍 How to Verify
Check if Vulnerable:
Check if running Lotos WebServer version 0.1.1 or earlier by examining version output or commit hashCheck Version:
./lotos --version or check commit hash in sourceVerify Fix Applied:
Verify version is newer than commit 3eb36cc and test with long URI requests to ensure no crashes📡 Detection & Monitoring
Log Indicators:
- Multiple connection resets
- Process crashes in system logs
- Unusually long URI requests in access logs
Network Indicators:
- HTTP requests with URIs exceeding 1024 characters
- Multiple TCP RST packets to web server port
SIEM Query:
source="web_logs" AND uri_length>1024 OR event="process_crash" AND process="lotos"