CVE-2025-24064
📋 TL;DR
This is a use-after-free vulnerability in DNS Server that allows unauthorized attackers to execute arbitrary code remotely. It affects systems running vulnerable DNS server software, potentially compromising entire networks through DNS traffic.
💻 Affected Systems
- Microsoft Windows DNS Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise leading to domain controller takeover, lateral movement across network, data exfiltration, and ransomware deployment.
Likely Case
DNS service disruption, denial of service, and potential foothold for further network exploitation.
If Mitigated
Limited to DNS service disruption if proper network segmentation and least privilege are implemented.
🎯 Exploit Status
Requires sending specially crafted DNS packets to vulnerable server. No authentication needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: To be specified in Microsoft Security Update
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-24064
Restart Required: Yes
Instructions:
1. Apply latest Windows Server security updates from Microsoft. 2. Restart DNS Server service or reboot server. 3. Verify patch installation via Windows Update history.
🔧 Temporary Workarounds
Restrict DNS Server Access
windowsLimit which hosts can query the DNS server using firewall rules
netsh advfirewall firewall add rule name="Restrict DNS" dir=in action=allow protocol=UDP localport=53 remoteip=192.168.1.0/24
Disable Recursive Queries
windowsConfigure DNS server to only answer authoritative queries for its zones
dnscmd /config /norecursion 1
🧯 If You Can't Patch
- Segment DNS servers from critical network segments using firewalls
- Implement network monitoring for anomalous DNS traffic patterns
🔍 How to Verify
Check if Vulnerable:
Check Windows Update history for missing security updates related to DNS ServerCheck Version:
systeminfo | findstr /B /C:"OS Name" /C:"OS Version"Verify Fix Applied:
Verify KB article for CVE-2025-24064 appears in installed updates list📡 Detection & Monitoring
Log Indicators:
- DNS Server Event ID 150 for unexpected shutdowns
- Windows Security Event ID 4688 for suspicious process creation
Network Indicators:
- Unusual DNS query patterns
- DNS responses with malformed data
- Traffic to DNS port 53 from unexpected sources
SIEM Query:
source="DNS" AND (query_length>512 OR response_contains="malformed")