CVE-2024-26190
📋 TL;DR
This vulnerability in Microsoft's QUIC protocol implementation allows attackers to cause denial of service by sending specially crafted network packets. It affects systems running Microsoft Windows with QUIC-enabled services. The vulnerability could crash affected services, disrupting legitimate traffic.
💻 Affected Systems
- Microsoft Windows
- Windows Server
📦 What is this software?
.net by Microsoft
.net by Microsoft
Powershell by Microsoft
Powershell by Microsoft
Windows 11 21h2 by Microsoft
Windows 11 22h2 by Microsoft
Windows 11 23h2 by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Complete service outage for QUIC-enabled applications, requiring service restart and potentially causing extended downtime for critical systems.
Likely Case
Temporary service disruption affecting QUIC traffic until the service recovers or is restarted, impacting application availability.
If Mitigated
Minimal impact with proper network segmentation and monitoring allowing quick detection and response to attack attempts.
🎯 Exploit Status
As a denial of service vulnerability in a network protocol, exploitation typically requires sending malformed packets to the vulnerable service.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft's monthly security updates for the specific KB article addressing CVE-2024-26190
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-26190
Restart Required: Yes
Instructions:
1. Apply the latest Windows security updates from Microsoft. 2. Restart affected systems to complete the patch installation. 3. Verify the patch is applied using Windows Update history or system information.
🔧 Temporary Workarounds
Disable QUIC Protocol
windowsTemporarily disable QUIC/HTTP3 support to mitigate the vulnerability while awaiting patches
netsh int http set clientcertnegotiation enable
Configure application settings to disable HTTP/3/QUIC
Network Segmentation
allRestrict access to QUIC-enabled services to trusted networks only
🧯 If You Can't Patch
- Implement network-level protections such as rate limiting and packet inspection to detect and block malicious QUIC traffic
- Monitor QUIC service health and implement automated restart procedures for affected services
🔍 How to Verify
Check if Vulnerable:
Check if QUIC/HTTP3 services are running and accessible on affected Windows systems. Review Windows Update history for missing security patches.Check Version:
wmic os get caption,version,buildnumberVerify Fix Applied:
Verify the specific KB patch for CVE-2024-26190 is installed via Windows Update history or 'wmic qfe list' command.📡 Detection & Monitoring
Log Indicators:
- Unexpected service crashes or restarts of QUIC-enabled services
- High volume of malformed QUIC packets in network logs
Network Indicators:
- Spike in QUIC protocol traffic from single sources
- Malformed QUIC packets in network captures
SIEM Query:
source="windows" AND (event_id=1000 OR event_id=1001) AND process_name contains "quic" OR "http3"