Source: security@qnapsecurity.com.tw
A generation of error message containing sensitive information vulnerability has been reported to affect HBS 3 Hybrid Backup Sync. If an attacker gains local network access, they can then exploit the vulnerability to read application data. We have already fixed the vulnerability in the following version: HBS 3 Hybrid Backup Sync 26.2.0.938 and later
HBS 3 Hybrid Backup Sync versions prior to 26.2.0.938 are vulnerable to a critical information disclosure flaw. An attacker with local network access can leverage this vulnerability to extract sensitive application data by triggering a specially crafted error message. This could lead to a complete compromise of the backup system and potentially the entire network.
Step 1: Network Access: The attacker must have local network access to the HBS 3 Hybrid Backup Sync instance. This could be achieved through various means, such as compromised credentials, physical access, or exploiting another vulnerability on the network. Step 2: Trigger Error Condition: The attacker identifies a specific action or input that triggers an error condition within HBS 3. This could involve sending malformed requests, attempting unauthorized operations, or providing invalid data. Step 3: Error Message Generation: The HBS 3 application processes the attacker's input and encounters the pre-defined error condition. The application then generates an error message to log the issue. Step 4: Sensitive Data Inclusion: The error message generation process inadvertently includes sensitive information, such as credentials or configuration details, within the error message. Step 5: Error Message Retrieval: The attacker retrieves the error message, either through direct access to the application logs, a network sniffer, or by observing the application's response. Step 6: Data Extraction: The attacker analyzes the error message and extracts the sensitive information, such as credentials, API keys, or other confidential data.
The vulnerability stems from the insecure generation of error messages within HBS 3. The application, when encountering specific error conditions, fails to sanitize or properly redact sensitive information before including it in the error message. This could involve database credentials, API keys, file paths, or other confidential data. The root cause likely lies in a lack of input validation or output encoding within the error handling routines. The specific function or logic flaw is likely within the error logging or reporting mechanisms, where sensitive data is directly concatenated into the error message string without proper sanitization. This is a classic example of an information leakage vulnerability.
While no specific APT groups are explicitly linked to this CVE, the nature of the vulnerability makes it attractive to various threat actors. The potential for data exfiltration and subsequent network compromise makes it a target for ransomware groups and state-sponsored actors. CISA KEV status is not applicable as the vulnerability is not explicitly listed.
Analyze HBS 3 application logs for unusual error messages containing sensitive information (e.g., database credentials, API keys, file paths).
Monitor network traffic for suspicious activity, such as attempts to access the HBS 3 application from unexpected sources or with unusual payloads.
Implement file integrity monitoring to detect unauthorized modifications to HBS 3 configuration files or data directories.
Use intrusion detection systems (IDS) and intrusion prevention systems (IPS) to identify and block malicious activity targeting the vulnerability. Look for patterns in network traffic that match known exploit attempts.
Review network traffic for unusual requests to the HBS 3 application, especially those that might trigger error conditions.
Upgrade HBS 3 Hybrid Backup Sync to version 26.2.0.938 or later.
Implement strong access controls to restrict network access to the HBS 3 application.
Regularly review and audit application logs for suspicious activity.
Implement a robust vulnerability management program to identify and address security vulnerabilities proactively.
Review and sanitize all error messages to remove sensitive information before release.
Implement input validation and output encoding to prevent information leakage.
Rotate any compromised credentials immediately.