CVE-2023-48676
📋 TL;DR
This vulnerability allows unauthorized users to access and manipulate sensitive information in Acronis Cyber Protect Cloud Agent for Windows due to missing authorization checks. It affects all Windows systems running Acronis Cyber Protect Cloud Agent versions before build 36943. Attackers could potentially read or modify protected data without proper credentials.
💻 Affected Systems
- Acronis Cyber Protect Cloud Agent
📦 What is this software?
Agent by Acronis
⚠️ Risk & Real-World Impact
Worst Case
Full compromise of protected backup data including exfiltration, deletion, or modification of sensitive files and system information stored by Acronis Cyber Protect Cloud.
Likely Case
Unauthorized access to backup metadata and configuration files, potentially exposing system information and backup schedules.
If Mitigated
Limited impact with proper network segmentation and access controls preventing unauthorized users from reaching the vulnerable agent.
🎯 Exploit Status
The vulnerability requires network access to the agent but no authentication, making it relatively easy to exploit for attackers with network access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Build 36943 or later
Vendor Advisory: https://security-advisory.acronis.com/advisories/SEC-5905
Restart Required: Yes
Instructions:
1. Open Acronis Cyber Protect Cloud Agent. 2. Check for updates in the agent interface. 3. Update to build 36943 or later. 4. Restart the system or agent service as prompted.
🔧 Temporary Workarounds
Network Segmentation
allRestrict network access to Acronis Cyber Protect Cloud Agent to only authorized management systems.
Windows Firewall Rules
windowsConfigure Windows Firewall to block inbound connections to the Acronis agent from unauthorized networks.
New-NetFirewallRule -DisplayName "Block Acronis Agent Access" -Direction Inbound -Program "C:\Program Files\Acronis\Agent\agent.exe" -Action Block
🧯 If You Can't Patch
- Implement strict network access controls to isolate Acronis agents from untrusted networks and users.
- Monitor agent logs for unauthorized access attempts and implement additional authentication layers if possible.
🔍 How to Verify
Check if Vulnerable:
Check the agent version in Acronis Cyber Protect Cloud Agent interface or look at the installed program version in Windows Programs and Features.Check Version:
wmic product where "name like 'Acronis%'" get versionVerify Fix Applied:
Verify the agent version is 36943 or higher and test that unauthorized users cannot access agent functions.📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to Acronis agent logs
- Unexpected connections to Acronis agent ports
- Failed authentication events followed by successful data access
Network Indicators:
- Unusual traffic patterns to Acronis agent default ports
- Connections from unauthorized IP addresses to agent services
SIEM Query:
source="acronis_logs" AND (event_type="unauthorized_access" OR (authentication="failed" AND subsequent_action="data_access"))