CVE-2021-25650
📋 TL;DR
A local privilege escalation vulnerability in Avaya Aura Utility Services allows authenticated local users to execute arbitrary scripts with elevated privileges. This affects all 7.x versions of the software, potentially compromising the entire system.
💻 Affected Systems
- Avaya Aura Utility Services
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise where an attacker gains root/administrator access, installs persistent backdoors, steals sensitive data, and pivots to other systems.
Likely Case
Local authenticated user escalates privileges to execute administrative commands, modify system configurations, or access restricted data.
If Mitigated
Limited impact with proper access controls, monitoring, and network segmentation preventing lateral movement.
🎯 Exploit Status
Requires local authenticated access and knowledge of script execution mechanisms in Avaya Aura Utility Services.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 8.0 or later
Vendor Advisory: https://support.avaya.com/css/P8/documents/101072728
Restart Required: Yes
Instructions:
1. Download the latest version (8.0+) from Avaya support portal. 2. Backup current configuration. 3. Install the update following Avaya's upgrade documentation. 4. Restart the Avaya Aura Utility Services.
🔧 Temporary Workarounds
Restrict local user access
linuxLimit which users have local access to systems running Avaya Aura Utility Services
# Review and restrict local user accounts
# Use sudoers file to limit privileged command execution
Monitor script execution
linuxImplement monitoring for unusual script execution patterns
# Set up auditd rules for script execution
# Monitor /tmp and other writable directories
🧯 If You Can't Patch
- Implement strict access controls to limit which users can access the affected systems
- Deploy enhanced monitoring and logging for privilege escalation attempts and unusual script execution
🔍 How to Verify
Check if Vulnerable:
Check the Avaya Aura Utility Services version. If it's any 7.x version, the system is vulnerable.Check Version:
# Check Avaya Aura Utility Services version via administrative interface or configuration filesVerify Fix Applied:
Verify the version is 8.0 or higher after applying the patch.📡 Detection & Monitoring
Log Indicators:
- Unusual script execution by non-privileged users
- Privilege escalation attempts in system logs
- Unexpected process execution with elevated privileges
Network Indicators:
- Unusual outbound connections from the affected system post-exploitation
SIEM Query:
source="avaya_logs" AND (event_type="privilege_escalation" OR process_name="suspicious_script")