CVE-2025-30412: Acronis Cyber Protect Auth Bypass Flaw

CVE-2025-30412 Overview

CVE-2025-30412 is a critical authentication bypass vulnerability affecting Acronis Cyber Protect products. This vulnerability allows sensitive data disclosure and manipulation due to improper authentication mechanisms in the affected software. Classified under CWE-1390 (Weak Authentication), this flaw enables unauthorized network-based attackers to bypass security controls without requiring any user interaction or privileges.

Critical Impact

Unauthenticated remote attackers can access and manipulate sensitive backup data, potentially compromising the confidentiality and integrity of protected systems across the organization.

Affected Products

• Acronis Cyber Protect 16 (Linux) before build 39938
• Acronis Cyber Protect 16 (Windows) before build 39938
• Acronis Cyber Protect 15 (Linux) before build 41800
• Acronis Cyber Protect 15 (Windows) before build 41800

Discovery Timeline

• 2026-02-20 - CVE-2025-30412 published to NVD
• 2026-02-20 - Last updated in NVD database

Technical Details for CVE-2025-30412

Vulnerability Analysis

This vulnerability stems from improper authentication mechanisms within Acronis Cyber Protect's network-accessible components. The flaw allows remote attackers to bypass authentication controls entirely, gaining unauthorized access to protected data and management functions. Because no user interaction or prior authentication is required, the attack surface is maximized for potential exploitation.

The vulnerability impacts both the confidentiality and integrity of data managed by Acronis Cyber Protect, with attackers able to both read sensitive backup data and potentially manipulate backup configurations or data itself. The changed scope indicator suggests that successful exploitation could impact resources beyond the vulnerable component, potentially affecting other systems protected by the backup solution.

Root Cause

The root cause is classified as CWE-1390: Weak Authentication. The authentication mechanism fails to properly validate user identity before granting access to sensitive operations and data. This implementation flaw allows attackers to circumvent authentication checks that should protect backup data and administrative functions.

Attack Vector

The attack is network-based and requires no authentication or user interaction. An attacker with network access to the Acronis Cyber Protect management interface can exploit this vulnerability remotely. The low attack complexity means that exploitation does not require specialized conditions or sophisticated techniques.

The vulnerability allows attackers to:

• Access sensitive backup data without credentials
• Potentially modify backup configurations
• Manipulate protected data within the backup infrastructure
• Impact systems beyond the immediate vulnerable component

Detection Methods for CVE-2025-30412

Indicators of Compromise

• Unusual authentication attempts or access patterns to Acronis Cyber Protect management interfaces
• Unauthorized access to backup data or configuration changes without corresponding valid user sessions
• Network traffic anomalies indicating unauthenticated API calls to protected endpoints
• Unexpected modifications to backup policies or protected system configurations

Detection Strategies

• Monitor Acronis Cyber Protect logs for authentication bypass indicators or sessions without valid credentials
• Implement network-level monitoring for suspicious traffic patterns to Acronis management ports
• Deploy intrusion detection rules to identify exploitation attempts targeting authentication mechanisms
• Audit backup data access logs for unauthorized retrieval or modification activities

Monitoring Recommendations

• Enable verbose logging on Acronis Cyber Protect servers to capture authentication events
• Configure SIEM alerts for authentication anomalies specific to backup infrastructure
• Implement network segmentation monitoring to detect lateral movement from compromised backup systems
• Establish baseline behavior for legitimate backup operations to identify deviations

How to Mitigate CVE-2025-30412

Immediate Actions Required

• Upgrade Acronis Cyber Protect 16 to build 39938 or later immediately
• Upgrade Acronis Cyber Protect 15 to build 41800 or later immediately
• Restrict network access to Acronis Cyber Protect management interfaces to trusted IP ranges only
• Review backup data and configurations for signs of unauthorized access or modification

Patch Information

Acronis has released security updates addressing this vulnerability. Detailed patch information is available in the Acronis Security Advisory SEC-8598. Organizations should prioritize patching given the critical severity and network-accessible nature of this vulnerability.

For Acronis Cyber Protect 16, update to build 39938 or later. For Acronis Cyber Protect 15, update to build 41800 or later. Both Linux and Windows platforms are affected and require patching.

Workarounds

• Implement strict network segmentation to limit access to Acronis Cyber Protect management interfaces
• Deploy a Web Application Firewall (WAF) or reverse proxy with additional authentication requirements
• Temporarily disable external network access to management interfaces until patching is complete
• Enable additional logging and monitoring to detect potential exploitation attempts

# Example: Restrict access to Acronis management interface via firewall
# Limit access to trusted management network only
iptables -A INPUT -p tcp --dport 9877 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 9877 -j DROP