CVE-2023-41726
📋 TL;DR
CVE-2023-41726 is a local privilege escalation vulnerability in Ivanti Avalanche caused by incorrect default permissions. An authenticated local attacker can exploit this to gain SYSTEM/root privileges on affected systems. This affects organizations using Ivanti Avalanche for enterprise device management.
💻 Affected Systems
- Ivanti Avalanche
📦 What is this software?
Avalanche by Ivanti
⚠️ Risk & Real-World Impact
Worst Case
An authenticated attacker gains full SYSTEM/root privileges, enabling complete system compromise, data theft, installation of persistent malware, and lateral movement across the network.
Likely Case
Malicious insider or compromised user account escalates to administrative privileges, allowing unauthorized access to sensitive device management data and systems.
If Mitigated
With proper network segmentation and least privilege access controls, impact is limited to the affected Avalanche server with minimal lateral movement potential.
🎯 Exploit Status
Requires local authenticated access to the Avalanche server. Exploitation likely involves manipulating file permissions or service configurations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 6.4.1.236
Vendor Advisory: https://download.wavelink.com/Files/avalanche_v6.4.1.236_release_notes.txt
Restart Required: Yes
Instructions:
1. Download Ivanti Avalanche version 6.4.1.236 from official sources. 2. Backup current configuration and data. 3. Run the installer to upgrade. 4. Restart the server as prompted.
🔧 Temporary Workarounds
Restrict Local Access
windowsLimit local login access to Avalanche servers to only authorized administrators
Review File Permissions
windowsAudit and tighten file/folder permissions on Avalanche installation directories
icacls "C:\Program Files\Wavelink\Avalanche" /inheritance:r /grant:r "Administrators:(OI)(CI)F" /grant:r "SYSTEM:(OI)(CI)F"
🧯 If You Can't Patch
- Implement strict access controls allowing only necessary administrative users to log into Avalanche servers
- Monitor for privilege escalation attempts using Windows Event Logs and implement alerting for suspicious activity
🔍 How to Verify
Check if Vulnerable:
Check Avalanche version in Control Panel > Programs and Features or via 'wmic product get name,version' commandCheck Version:
wmic product where "name like '%Avalanche%'" get name,versionVerify Fix Applied:
Verify version is 6.4.1.236 or later and check that file permissions on Avalanche directories are properly restricted📡 Detection & Monitoring
Log Indicators:
- Windows Event ID 4688 (process creation) showing unexpected privilege escalation
- Security log entries showing users gaining SYSTEM privileges
Network Indicators:
- Unusual administrative connections from non-admin user accounts to network resources
SIEM Query:
source="windows_security" EventID=4688 NewProcessName="*" SubjectUserName!="SYSTEM" TokenElevationType="%%1936"