CVE-2026-28715: Acronis Cyber Protect Info Disclosure Bug

CVE-2026-28715 Overview

CVE-2026-28715 is a sensitive information disclosure vulnerability in Acronis Cyber Protect 17 caused by improper authorization checks. This vulnerability, classified under CWE-863 (Incorrect Authorization), allows authenticated attackers to access sensitive information that should be restricted based on proper authorization controls. The flaw affects Acronis Cyber Protect 17 installations on both Linux and Windows platforms prior to build 41186.

Critical Impact

Authenticated attackers can exploit improper authorization checks to access sensitive information, potentially exposing confidential backup data, credentials, or system configurations managed by Acronis Cyber Protect.

Affected Products

• Acronis Cyber Protect 17 (Linux) before build 41186
• Acronis Cyber Protect 17 (Windows) before build 41186

Discovery Timeline

• 2026-03-06 - CVE-2026-28715 published to NVD
• 2026-03-12 - Last updated in NVD database

Technical Details for CVE-2026-28715

Vulnerability Analysis

This vulnerability stems from improper authorization checks within Acronis Cyber Protect 17. The application fails to properly validate user permissions before granting access to sensitive resources, allowing authenticated users with lower privileges to access information they should not be authorized to view. The network-based attack vector means exploitation can occur remotely, though it requires the attacker to have valid credentials (low-privilege authentication) to the target system.

The vulnerability impacts confidentiality without affecting integrity or availability, meaning attackers can read sensitive data but cannot modify or delete it through this specific flaw.

Root Cause

The root cause of CVE-2026-28715 is CWE-863 (Incorrect Authorization). The application performs authorization checks incorrectly, failing to properly enforce access control policies. This allows authenticated users to bypass intended restrictions and access data or functionality reserved for users with higher privilege levels.

Attack Vector

The attack can be executed over the network with low complexity. An attacker requires low-privilege authentication to the Acronis Cyber Protect system. Once authenticated, the attacker can exploit the improper authorization checks to access sensitive information such as backup configurations, protected data references, or system settings that should require elevated permissions.

The exploitation does not require user interaction, making it straightforward for an authenticated attacker to discover and abuse. Organizations should be particularly concerned about insider threats or scenarios where attackers have obtained low-privilege credentials through phishing or credential stuffing attacks.

Detection Methods for CVE-2026-28715

Indicators of Compromise

• Unusual access patterns to sensitive backup configurations or data by low-privilege user accounts
• Unexpected API calls or requests to administrative endpoints from non-administrative users
• Anomalous data access events in Acronis Cyber Protect logs indicating privilege boundary violations

Detection Strategies

• Monitor Acronis Cyber Protect access logs for authorization failures followed by successful unauthorized data access
• Implement alerts for low-privilege accounts accessing resources typically reserved for administrators
• Review audit logs for unusual patterns of sensitive data retrieval by standard user accounts

Monitoring Recommendations

• Enable verbose logging within Acronis Cyber Protect to capture detailed authorization events
• Deploy SIEM rules to correlate authentication events with subsequent data access patterns
• Establish baseline behavior profiles for user accounts to identify anomalous access activities

How to Mitigate CVE-2026-28715

Immediate Actions Required

• Upgrade Acronis Cyber Protect 17 to build 41186 or later immediately
• Audit existing user accounts and remove unnecessary privileges pending patch deployment
• Review access logs for potential prior exploitation of this vulnerability

Patch Information

Acronis has released a security update addressing this vulnerability in Acronis Cyber Protect 17 build 41186. Organizations should apply this update immediately to remediate the improper authorization checks. For detailed patch information and download links, refer to the Acronis Security Advisory SEC-5910.

Workarounds

• Implement network segmentation to limit exposure of Acronis Cyber Protect management interfaces
• Restrict access to Acronis Cyber Protect to only essential personnel with verified business needs
• Deploy additional monitoring on Acronis Cyber Protect servers to detect exploitation attempts until patching is complete
• Consider temporarily disabling remote access to the management console if operationally feasible

# Example: Restrict network access to Acronis Cyber Protect management port (adjust port as needed)
# Linux iptables rule to limit access to trusted management network
iptables -A INPUT -p tcp --dport 9877 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 9877 -j DROP