CVE-2026-5601: Acrel Electrical Information Disclosure

CVE-2026-5601 Overview

A vulnerability has been identified in Acrel Electrical Prepaid Cloud Platform version 1.0 that affects the Backup File Handler component. This security flaw involves improper handling of the /bin.rar file, leading to information disclosure. The vulnerability can be exploited remotely without requiring authentication, potentially exposing sensitive backup data to unauthorized attackers.

Critical Impact

This information disclosure vulnerability allows remote attackers to access backup files containing potentially sensitive configuration data, credentials, or other confidential information from the Acrel Electrical Prepaid Cloud Platform.

Affected Products

• Acrel Electrical Prepaid Cloud Platform 1.0
• Backup File Handler component (/bin.rar)

Discovery Timeline

• 2026-04-05 - CVE-2026-5601 published to NVD
• 2026-04-07 - Last updated in NVD database

Technical Details for CVE-2026-5601

Vulnerability Analysis

This vulnerability is classified under CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor). The Backup File Handler component in Acrel Electrical Prepaid Cloud Platform 1.0 fails to properly restrict access to backup archive files. When the /bin.rar file endpoint is accessed, the application does not enforce adequate authentication or authorization controls, allowing unauthenticated remote attackers to retrieve backup data.

The exploit has been publicly disclosed, and the vendor was contacted during responsible disclosure but did not respond. This lack of vendor engagement means no official patch is currently available, leaving systems running this platform vulnerable to exploitation.

Root Cause

The root cause of this vulnerability lies in missing access controls on the Backup File Handler component. The application exposes the /bin.rar backup archive file without requiring proper authentication, authorization checks, or access restrictions. This design flaw allows any network-accessible attacker to download potentially sensitive backup data directly from the platform.

Attack Vector

The attack can be launched remotely over the network without any user interaction or special privileges required. An attacker simply needs network access to the vulnerable Acrel Electrical Prepaid Cloud Platform instance to exploit this vulnerability.

The attack flow involves:

1. Attacker identifies an exposed Acrel Electrical Prepaid Cloud Platform instance
2. Attacker sends a direct HTTP request to the /bin.rar endpoint
3. The server responds with the backup archive file without verifying authorization
4. Attacker extracts potentially sensitive information from the downloaded backup

For detailed technical information, refer to the GitHub CVE Report and VulDB Vulnerability #355393.

Detection Methods for CVE-2026-5601

Indicators of Compromise

• Unexpected HTTP requests to /bin.rar or similar backup file endpoints
• Large outbound data transfers containing archive file signatures (.rar, .zip)
• Access logs showing unauthenticated requests to backup-related paths
• Unusual download activity from the platform's file serving endpoints

Detection Strategies

• Monitor web server access logs for requests targeting /bin.rar or backup file paths
• Implement network traffic analysis to detect large file downloads from cloud platform endpoints
• Configure intrusion detection systems (IDS) to alert on RAR archive file transfers from critical infrastructure systems
• Review authentication logs for missing or failed authentication attempts followed by successful file access

Monitoring Recommendations

• Enable detailed logging on the Acrel Electrical Prepaid Cloud Platform for all file access operations
• Configure SIEM rules to correlate backup file access with authentication events
• Implement file integrity monitoring on backup storage directories
• Set up alerts for any access to backup archive files from external IP addresses

How to Mitigate CVE-2026-5601

Immediate Actions Required

• Restrict network access to the Acrel Electrical Prepaid Cloud Platform using firewall rules or network segmentation
• Block external access to the /bin.rar endpoint and any other backup file paths
• Implement web application firewall (WAF) rules to deny requests to sensitive file paths
• Audit backup file locations and remove or relocate publicly accessible backup archives

Patch Information

No official vendor patch is currently available. The vendor was contacted during responsible disclosure but did not respond. Organizations should implement network-level mitigations and monitor for any future security updates from Acrel. Additional vulnerability details can be found at VulDB Submission #784693.

Workarounds

• Deploy a reverse proxy or WAF in front of the platform to filter requests to backup file endpoints
• Implement IP-based access control lists (ACLs) limiting access to trusted administrative networks only
• Move backup files to a non-web-accessible storage location
• If platform access is not required externally, isolate the system on an internal network segment only

# Example: Block access to backup files using iptables (adjust as needed)
# Block external access to the web server port for unauthorized IPs
iptables -A INPUT -p tcp --dport 80 -s ! 10.0.0.0/8 -j DROP
iptables -A INPUT -p tcp --dport 443 -s ! 10.0.0.0/8 -j DROP

# Example: Nginx configuration to deny access to backup files
# Add to server block
location ~* \.(rar|zip|bak|backup)$ {
    deny all;
    return 403;
}