CVE-2023-52266
📋 TL;DR
CVE-2023-52266 is a use-after-free vulnerability in ehttp 1.0.6's epoll_socket.cpp read_func. An attacker can trigger this by making many connections over a short time, potentially leading to remote code execution or denial of service. This affects systems running vulnerable versions of the ehttp library.
💻 Affected Systems
- ehttp
📦 What is this software?
Ehttp by Hongliuliao
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise
Likely Case
Denial of service causing application crashes or instability
If Mitigated
Limited impact with proper network segmentation and rate limiting
🎯 Exploit Status
Exploitation requires making many connections quickly; no public exploit code available
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Commit 17405b975948abc216f6a085d2d027ec1cfd5766 or later
Vendor Advisory: https://github.com/hongliuliao/ehttp/commit/17405b975948abc216f6a085d2d027ec1cfd5766
Restart Required: Yes
Instructions:
1. Update ehttp to commit 17405b975948abc216f6a085d2d027ec1cfd5766 or later
2. Recompile any applications using ehttp
3. Restart affected services
🔧 Temporary Workarounds
Connection Rate Limiting
linuxLimit the rate of incoming connections to prevent triggering the vulnerability
iptables -A INPUT -p tcp --dport <PORT> -m limit --limit 10/second -j ACCEPT
iptables -A INPUT -p tcp --dport <PORT> -j DROP
🧯 If You Can't Patch
- Implement network segmentation to isolate vulnerable systems
- Deploy web application firewall with connection rate limiting rules
🔍 How to Verify
Check if Vulnerable:
Check ehttp version or commit hash; if using version 1.0.6 before commit 17405b975948abc216f6a085d2d027ec1cfd5766, you are vulnerableCheck Version:
Check the git commit hash or version in your ehttp installationVerify Fix Applied:
Verify ehttp is at commit 17405b975948abc216f6a085d2d027ec1cfd5766 or later📡 Detection & Monitoring
Log Indicators:
- Multiple connection attempts from single IP in short timeframe
- Application crashes or segmentation faults
Network Indicators:
- High volume of TCP connections to ehttp port
- Connection attempts exceeding normal patterns
SIEM Query:
source="ehttp" AND (event="crash" OR event="segfault") OR source="firewall" AND dest_port=<ehttp_port> AND connection_count > 1000