CVE-2026-2864: SSM-ERP Path Traversal Vulnerability

CVE-2026-2864 Overview

A path traversal vulnerability has been identified in the ssm-erp and production_ssm projects (distributed under two different names by feng_ha_ha/megagao). This vulnerability affects the pictureDelete function within the PictureController.java file, where improper handling of the picName argument enables attackers to traverse file system directories and potentially delete arbitrary files on the server.

Critical Impact

Remote attackers can exploit this path traversal flaw to manipulate file operations outside the intended directory, potentially leading to unauthorized file deletion, data loss, or system compromise through file system manipulation.

Affected Products

• ssm-erp (feng_ha_ha/megagao) up to commit 4288d53bd35757b27f2d070057aefb2c07bdd097
• production_ssm (feng_ha_ha/megagao) up to commit 4288d53bd35757b27f2d070057aefb2c07bdd097

Discovery Timeline

• 2026-02-21 - CVE-2026-2864 published to NVD
• 2026-02-23 - Last updated in NVD database

Technical Details for CVE-2026-2864

Vulnerability Analysis

This path traversal vulnerability (CWE-22) exists in the pictureDelete function of PictureController.java. The application fails to properly sanitize user-supplied input in the picName parameter before using it in file system operations. When processing file deletion requests, the controller does not validate that the specified file path remains within the expected directory boundaries.

The vulnerability allows authenticated attackers to craft malicious requests containing directory traversal sequences (such as ../) in the picName parameter. By manipulating this input, an attacker can escape the intended picture storage directory and reference files in other locations on the server's file system. The network-based attack vector requires low privileges to execute, and no user interaction is necessary for exploitation.

The exploit has been publicly disclosed, which increases the risk of active exploitation. Notably, this product does not use versioning, making it difficult to determine specific affected releases. The project maintainers were notified through an issue report but have not yet responded.

Root Cause

The root cause of this vulnerability is insufficient input validation in the pictureDelete function. The picName argument is passed directly to file system operations without proper sanitization or canonicalization. The application fails to:

1. Validate that the file path does not contain path traversal sequences (../, ..\, etc.)
2. Canonicalize the path before checking directory boundaries
3. Implement a whitelist approach for acceptable file locations

Attack Vector

The attack can be launched remotely over the network against systems running vulnerable versions of ssm-erp or production_ssm. An authenticated attacker with low-level privileges can send specially crafted HTTP requests to the picture deletion endpoint, including malicious path traversal sequences in the picName parameter. This allows the attacker to reference and potentially delete files outside the designated picture storage directory.

The vulnerability details and proof-of-concept information have been documented in the GitHub Issue Discussion and tracked in the VulDB Entry #347103.

Detection Methods for CVE-2026-2864

Indicators of Compromise

• Suspicious HTTP requests to picture deletion endpoints containing path traversal sequences (../, ..%2f, %2e%2e/, etc.) in the picName parameter
• Unexpected file deletions outside the designated picture storage directories
• Web server access logs showing repeated attempts to manipulate file paths with directory traversal patterns
• Application error logs indicating file operations attempting to access unauthorized directories

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block path traversal patterns in request parameters
• Monitor application logs for file system access errors indicating out-of-bounds access attempts
• Deploy intrusion detection systems (IDS) with signatures for common path traversal attack patterns
• Audit file system integrity to detect unexpected file deletions or modifications

Monitoring Recommendations

• Enable verbose logging on the PictureController endpoints to capture all file operation requests
• Set up alerts for any file operations that reference parent directory sequences
• Monitor for anomalous deletion patterns, particularly affecting system or configuration files
• Track authentication events correlated with picture deletion requests to identify compromised accounts

How to Mitigate CVE-2026-2864

Immediate Actions Required

• Review and audit all deployments of ssm-erp and production_ssm for exposure to this vulnerability
• Implement input validation on the picName parameter to reject path traversal sequences before processing
• Apply a web application firewall (WAF) rule to block requests containing directory traversal patterns
• Restrict file system permissions for the application to limit access to only necessary directories
• Monitor the GitHub repository for updates from the project maintainers

Patch Information

No official patch is currently available. The project maintainers were notified of the vulnerability through an issue report but have not responded yet. This product does not use versioning, which makes tracking fixed releases difficult. Organizations should implement mitigations at the application or network layer until an official fix is released.

Workarounds

• Implement a custom input sanitization filter that canonicalizes file paths and validates they remain within allowed directories
• Deploy a reverse proxy or WAF with rules to detect and block path traversal patterns in the picName parameter
• Restrict network access to the vulnerable endpoints to trusted internal networks only
• Disable the picture deletion functionality if not critical to business operations
• Consider forking the repository and applying custom security patches to the PictureController.java file

# Example WAF rule to block path traversal in requests (ModSecurity format)
SecRule ARGS:picName "@contains ../" "id:1001,phase:2,deny,status:403,msg:'Path Traversal Attempt Detected'"
SecRule ARGS:picName "@contains ..\\" "id:1002,phase:2,deny,status:403,msg:'Path Traversal Attempt Detected'"
SecRule ARGS:picName "@rx (?i)(?:%2e%2e%2f|%2e%2e/|\.%2e/|%2e\./)+" "id:1003,phase:2,deny,status:403,msg:'Encoded Path Traversal Attempt'"