CVE-2026-0705: Acronis Cloud Manager Privilege Escalation

CVE-2026-0705 Overview

CVE-2026-0705 is a local privilege escalation vulnerability affecting Acronis Cloud Manager for Windows. The vulnerability stems from insecure folder permissions (CWE-276: Incorrect Default Permissions), which allows a local attacker with low privileges to potentially escalate their privileges on the affected system. This type of vulnerability is particularly concerning in enterprise environments where multiple users may have access to the same system.

Critical Impact

Local attackers with limited privileges can exploit insecure folder permissions to escalate privileges, potentially gaining full control over the affected Windows system running Acronis Cloud Manager.

Affected Products

• Acronis Cloud Manager (Windows) before build 6.4.25342.354

Discovery Timeline

• 2026-01-27 - CVE-2026-0705 published to NVD
• 2026-01-29 - Last updated in NVD database

Technical Details for CVE-2026-0705

Vulnerability Analysis

This vulnerability is classified under CWE-276 (Incorrect Default Permissions), indicating that the affected Acronis Cloud Manager installation creates folders or directories with overly permissive access controls. The vulnerability requires local access and user interaction to exploit, making it more complex to leverage in real-world scenarios. However, successful exploitation could result in high impact across confidentiality, integrity, and availability of the affected system.

The attack complexity is considered high due to the specific conditions required for exploitation, and user interaction is needed. Despite these mitigating factors, the potential for complete system compromise through privilege escalation makes this a significant security concern for organizations running vulnerable versions.

Root Cause

The root cause of CVE-2026-0705 lies in the improper configuration of file system permissions during the installation or operation of Acronis Cloud Manager on Windows systems. When folders are created with insufficiently restrictive permissions, local users may be able to write malicious files or modify existing files within protected directories, enabling privilege escalation attacks.

Attack Vector

The attack vector for this vulnerability is local, meaning an attacker must already have some level of access to the target system. The exploitation scenario typically involves:

1. A low-privileged user identifying directories within the Acronis Cloud Manager installation that have weak permissions
2. Placing malicious executables or scripts in these directories
3. Waiting for or triggering a privileged process to execute the malicious code
4. Gaining elevated privileges on the system

The vulnerability exploits the trust relationship between the application's privileged processes and the file system locations they interact with. When these locations are writable by unprivileged users, the security boundary is compromised.

Detection Methods for CVE-2026-0705

Indicators of Compromise

• Unexpected files or executables appearing in Acronis Cloud Manager installation directories
• Modified timestamps on files within the Acronis installation folder that don't correlate with legitimate updates
• Evidence of privilege escalation attempts in Windows Security Event logs (Event ID 4688, 4672)

Detection Strategies

• Audit file system permissions on Acronis Cloud Manager installation directories using tools like icacls or PowerShell's Get-Acl
• Monitor for unusual process creation events where child processes have higher privileges than parent processes
• Deploy endpoint detection and response (EDR) solutions to identify suspicious file modifications in application directories

Monitoring Recommendations

• Enable Windows Security auditing for object access and process creation events
• Implement file integrity monitoring (FIM) on critical application directories
• Review Acronis Cloud Manager logs for unusual service behavior or unexpected restarts

How to Mitigate CVE-2026-0705

Immediate Actions Required

• Update Acronis Cloud Manager to build 6.4.25342.354 or later immediately
• Audit current folder permissions on Acronis Cloud Manager installation directories
• Review system logs for any evidence of prior exploitation attempts
• Restrict local access to systems running vulnerable versions until patching is complete

Patch Information

Acronis has addressed this vulnerability in Acronis Cloud Manager build 6.4.25342.354. Organizations should upgrade to this version or later to remediate the vulnerability. For detailed patch information, refer to the Acronis Security Advisory SEC-7316.

Workarounds

• Manually restrict folder permissions on Acronis Cloud Manager directories to limit write access to administrators only
• Apply the principle of least privilege to limit which users have local access to affected systems
• Use Windows Group Policy to enforce strict file system permissions on application directories

# Example: Check and fix folder permissions using icacls (Windows)
# Review current permissions
icacls "C:\Program Files\Acronis\CloudManager" /T

# Remove inherited permissions and grant access only to Administrators and SYSTEM
icacls "C:\Program Files\Acronis\CloudManager" /inheritance:r /grant:r "BUILTIN\Administrators:(OI)(CI)F" /grant:r "NT AUTHORITY\SYSTEM:(OI)(CI)F"