CVE-2026-27630
📋 TL;DR
TinyWeb versions before 2.02 are vulnerable to Slowloris denial-of-service attacks where attackers can exhaust server resources by opening many connections and sending data extremely slowly. Anyone hosting services with vulnerable TinyWeb versions is affected. The vulnerability allows unauthenticated remote attackers to make the web server unresponsive.
💻 Affected Systems
- TinyWeb
📦 What is this software?
Tinyweb by Ritlabs
⚠️ Risk & Real-World Impact
Worst Case
Complete service outage making the web server completely unresponsive to legitimate users, potentially for extended periods until manual intervention.
Likely Case
Service degradation or intermittent unavailability as server resources are consumed by malicious connections.
If Mitigated
Minimal impact with proper connection limits and timeouts enforced via patching or reverse proxy.
🎯 Exploit Status
Slowloris is a well-known attack technique with many public tools available. No authentication required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.02
Vendor Advisory: https://github.com/maximmasiutin/TinyWeb/security/advisories/GHSA-ccv5-8948-c99c
Restart Required: Yes
Instructions:
1. Download TinyWeb version 2.02 or later from the official repository. 2. Replace the existing TinyWeb executable with the patched version. 3. Restart the TinyWeb service or process.
🔧 Temporary Workarounds
Reverse Proxy with Connection Limits
allPlace TinyWeb behind a reverse proxy like nginx or HAProxy that enforces connection limits and timeouts
# nginx example configuration
worker_processes auto;
events {
worker_connections 1024;
}
http {
proxy_read_timeout 30s;
proxy_connect_timeout 30s;
proxy_send_timeout 30s;
# ... rest of configuration
🧯 If You Can't Patch
- Deploy a Web Application Firewall (WAF) like Cloudflare or ModSecurity configured to detect and block Slowloris patterns
- Implement network-level controls such as rate limiting or connection limiting at the firewall/load balancer
🔍 How to Verify
Check if Vulnerable:
Check if TinyWeb version is below 2.02. The vulnerability exists if no connection limits or idle timeouts are configured.Check Version:
Check the TinyWeb executable properties or run it with --version flag if availableVerify Fix Applied:
Verify TinyWeb version is 2.02 or higher and check that CMaxConnections and CConnectionTimeoutSecs parameters are properly configured.📡 Detection & Monitoring
Log Indicators:
- Large number of simultaneous connections from single IPs
- Connections remaining open for unusually long periods without completing requests
- Server resource exhaustion warnings
Network Indicators:
- Multiple TCP connections from same source with very slow data transmission
- Incomplete HTTP requests that never finish
- Abnormally high number of concurrent connections
SIEM Query:
source="tinyweb.log" AND (connection_count > 500 OR connection_duration > 300)