CVE-2024-26261: Hgiga OAKlouds Path Traversal Flaw

CVE-2024-26261 Overview

CVE-2024-26261 is a critical Path Traversal vulnerability affecting HGiga OAKlouds' file download functionality in certain modules. The vulnerability allows unauthenticated attackers to manipulate request parameters to read arbitrary files from the affected system. More significantly, the file is automatically deleted after being downloaded, creating both a confidentiality and availability impact.

This vulnerability is particularly dangerous as it combines arbitrary file read with automatic file deletion, enabling attackers to exfiltrate sensitive data while simultaneously destroying evidence or disrupting system operations—all without requiring authentication.

Critical Impact

Unauthenticated attackers can remotely read and delete any file on the system by manipulating file path parameters, potentially leading to complete system compromise and data destruction.

Affected Products

• HGiga OAKlouds-Organization 2.0
• HGiga OAKlouds-Organization 3.0
• HGiga OAKlouds-Webbase 2.0
• HGiga OAKlouds-Webbase 3.0

Discovery Timeline

• 2024-02-15 - CVE-2024-26261 published to NVD
• 2025-01-23 - Last updated in NVD database

Technical Details for CVE-2024-26261

Vulnerability Analysis

The vulnerability resides in the file download functionality of HGiga OAKlouds modules. This Path Traversal (CWE-22) flaw exists because the application fails to properly validate and sanitize user-supplied file path parameters before processing file download requests.

An attacker can exploit this vulnerability by injecting path traversal sequences (such as ../) into specific request parameters used by the file download functionality. The application processes these malicious paths without proper sanitization, allowing access to files outside the intended directory structure.

The exploitation requires no authentication, making this vulnerability accessible to any network-based attacker. Once exploited, the attacker can download arbitrary files from the server, potentially accessing configuration files, database credentials, source code, or other sensitive data. The automatic deletion of files after download compounds the severity, as attackers can simultaneously exfiltrate data and disrupt system operations.

Root Cause

The root cause of this vulnerability is improper input validation (CWE-22: Improper Limitation of a Pathname to a Restricted Directory). The file download functionality accepts user-controlled input for file path parameters without adequately validating that the requested path remains within the intended directory boundaries. This allows attackers to use relative path sequences to traverse the directory structure and access files anywhere on the file system that the application has read permissions for.

Additionally, the design flaw of automatically deleting files after download exacerbates the impact, transforming what would be a file disclosure issue into a combined read-and-destroy vulnerability.

Attack Vector

The attack is conducted over the network and requires no user interaction or authentication. An attacker can craft malicious HTTP requests targeting the vulnerable file download endpoints, inserting path traversal sequences into the file path parameters.

The attack flow typically involves:

1. Identifying the vulnerable file download endpoint in the OAKlouds application
2. Crafting a request with path traversal sequences in the file path parameter
3. Sending the malicious request to download sensitive system files
4. The application processes the request, returns the file contents, and then deletes the file

This vulnerability is particularly dangerous in environments where the OAKlouds application runs with elevated privileges, as it could allow access to system-critical files such as /etc/passwd, /etc/shadow, configuration files, or application credentials.

Detection Methods for CVE-2024-26261

Indicators of Compromise

• HTTP requests to file download endpoints containing path traversal sequences such as ../, ..%2f, %2e%2e/, or encoded variants
• Unusual access patterns to the file download functionality from external IP addresses
• Missing system or application files that were unexpectedly deleted
• Log entries showing access to sensitive file paths through the download functionality

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block path traversal patterns in request parameters
• Monitor HTTP access logs for requests containing directory traversal sequences targeting download endpoints
• Deploy file integrity monitoring (FIM) solutions to detect unexpected file deletions on the server
• Enable detailed application logging to capture all file access and download requests for forensic analysis

Monitoring Recommendations

• Configure real-time alerting for any HTTP requests containing path traversal patterns
• Monitor for sudden or unexplained file deletions on systems running HGiga OAKlouds
• Track authentication bypass attempts and unauthenticated access to administrative endpoints
• Implement network traffic analysis to identify data exfiltration patterns from OAKlouds servers

How to Mitigate CVE-2024-26261

Immediate Actions Required

• Restrict network access to HGiga OAKlouds installations to trusted IP addresses only
• Place a web application firewall (WAF) in front of the application to filter path traversal attempts
• Review and audit recent file download activity for signs of exploitation
• Consider temporarily disabling the file download functionality until patches are applied

Patch Information

Organizations should contact HGiga directly for patching information and security updates. Additional details may be available from the TWCert Security Announcement and the CHT Security News Update.

Workarounds

• Implement strict input validation at the network perimeter using a WAF to block requests containing path traversal sequences
• Restrict file system permissions for the OAKlouds application to minimize the scope of accessible files
• Segment the network to limit attacker access to OAKlouds installations from untrusted networks
• Enable comprehensive logging and monitoring to detect exploitation attempts while awaiting a vendor patch

# Example WAF rule to block path traversal attempts
# ModSecurity rule configuration
SecRule REQUEST_URI|ARGS|ARGS_NAMES "@rx (\.\./|\.\.\\|%2e%2e%2f|%2e%2e/|\.\.%2f|%252e%252e%252f)" \
    "id:1001,phase:2,deny,status:403,msg:'Path Traversal Attempt Blocked'"