CVE-2024-26186
📋 TL;DR
This vulnerability in Microsoft SQL Server Native Scoring allows remote attackers to execute arbitrary code on affected systems. Attackers can exploit this use-after-free vulnerability to gain SYSTEM privileges on the target server. Organizations running vulnerable versions of SQL Server are affected.
💻 Affected Systems
- Microsoft SQL Server
📦 What is this software?
Sql 2016 Azure Connect Feature Pack by Microsoft
View all CVEs affecting Sql 2016 Azure Connect Feature Pack →
Sql Server 2016 by Microsoft
Sql Server 2017 by Microsoft
Sql Server 2017 by Microsoft
Sql Server 2019 by Microsoft
Sql Server 2019 by Microsoft
Sql Server 2022 by Microsoft
Sql Server 2022 by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with SYSTEM privileges, enabling data theft, ransomware deployment, lateral movement, and persistent backdoor installation.
Likely Case
Remote code execution leading to database compromise, credential theft, and potential lateral movement within the network.
If Mitigated
Limited impact due to network segmentation, least privilege configurations, and proper patch management.
🎯 Exploit Status
Requires authentication to SQL Server. The vulnerability is in a use-after-free condition (CWE-416) that can be triggered through specially crafted requests.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Microsoft's monthly security updates for February 2024 or later
Vendor Advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-26186
Restart Required: Yes
Instructions:
1. Download the latest security update from Microsoft Update Catalog. 2. Apply the patch to all affected SQL Server instances. 3. Restart SQL Server services. 4. Test application functionality after patching.
🔧 Temporary Workarounds
Disable Native Scoring
windowsDisable the vulnerable Native Scoring feature if not required for business operations
-- Requires SQL Server configuration changes
-- Consult Microsoft documentation for specific steps
Network Segmentation
allRestrict network access to SQL Server instances using firewalls and network segmentation
-- Configure Windows Firewall to restrict SQL Server ports
-- Implement network segmentation to isolate SQL servers
🧯 If You Can't Patch
- Implement strict network access controls to limit connections to SQL Server
- Apply principle of least privilege to SQL Server service accounts and database users
🔍 How to Verify
Check if Vulnerable:
Check SQL Server version and compare against Microsoft's security advisory for affected versionsCheck Version:
SELECT @@VERSION;Verify Fix Applied:
Verify SQL Server version is updated to a patched version and check that security update is installed via Windows Update history📡 Detection & Monitoring
Log Indicators:
- Unusual authentication attempts to SQL Server
- Failed login attempts followed by successful exploitation
- Suspicious process creation from SQL Server service account
Network Indicators:
- Unusual network traffic patterns to SQL Server ports
- Suspicious SQL queries attempting to trigger the vulnerability
SIEM Query:
Example: (event_source="SQL Server" AND (event_id=18456 OR event_id=18454)) OR (process_name="sqlservr.exe" AND parent_process!="services.exe")