OpenMage LTS has a Path Traversal Filter Bypass in Dataflow Module

The Dataflow module in OpenMage LTS uses a weak blacklist filter (str_replace('../', '', $input)) to prevent path traversal attacks. This filter can be bypassed using patterns like ..././ or ....//, which after the replacement still result in ../. An authenticated administrator can exploit this to read arbitrary files from the server filesystem.

Metric	Value	Justification
Attack Vector (AV)	Network	Exploitable via admin panel
Attack Complexity (AC)	Low	Simple bypass pattern
Privileges Required (PR)	High	Requires admin authentication
User Interaction (UI)	None	No additional user interaction needed
Scope (S)	Unchanged	Impacts the vulnerable component
Confidentiality (C)	High	Can read sensitive system files
Integrity (I)	None	Read-only vulnerability
Availability (A)	None	No impact on availability

Affected Products

• OpenMage LTS versions < 20.16.1
• All versions derived from Magento 1.x with these code paths

Affected Files

File	Line	Vulnerable Code
app/code/core/Mage/Dataflow/Model/Convert/Parser/Csv.php	67	str_replace('../', '', urldecode(...))
app/code/core/Mage/Dataflow/Model/Convert/Parser/Xml/Excel.php	63	str_replace('../', '', urldecode(...))

Vulnerability Details

The Dataflow module allows administrators to import data from files. The files parameter specifies which file to import from the var/import/ directory. To prevent path traversal, the code uses str_replace() to remove ../ sequences:

$file = Mage::app()->getConfig()->getTempVarDir() . '/import/'
    . str_replace('../', '', urldecode(Mage::app()->getRequest()->getParam('files')));

However, str_replace() only performs a single pass, making it trivially bypassable:

Bypass Examples

Input	After str_replace('../', '', ...)	Result
..././	../	Bypass
....//	../	Bypass
..././..././..././etc/passwd	../../../etc/passwd	File read

Attack Scenario

1. Attacker gains admin access (via compromised credentials, social engineering, etc.)
2. Navigate to System > Import/Export > Dataflow Profiles
3. Create or modify an import profile
4. Set the files parameter to: ..././..././..././etc/passwd
5. Run the profile to read the contents of /etc/passwd

Proof of Concept

# Request to Dataflow with bypass pattern
GET /admin/system_convert_gui/run/id/1/?files=..././..././..././etc/passwd

# The str_replace removes '../' leaving:
# ..././..././..././etc/passwd -> ../../../etc/passwd

# Final path resolves to:
# /var/www/html/var/import/../../../etc/passwd -> /etc/passwd

Remediation

Replace the weak str_replace() filter with basename() to extract only the filename:

// Before (vulnerable)
$file = Mage::app()->getConfig()->getTempVarDir() . '/import/'
    . str_replace('../', '', urldecode(Mage::app()->getRequest()->getParam('files')));

// After (fixed)
$file = Mage::app()->getConfig()->getTempVarDir() . '/import/'
    . basename(urldecode(Mage::app()->getRequest()->getParam('files')));

Using basename() ensures only the filename portion is used, completely preventing any path traversal regardless of the input pattern.

Workarounds

If immediate upgrade is not possible:

1. Restrict admin access: Limit Dataflow access to trusted administrators only
2. Disable Dataflow: If not in use, disable the Dataflow module entirely
3. Web Application Firewall: Block requests containing path traversal patterns
4. File permissions: Ensure the web server user has minimal filesystem permissions
5. Monitor admin activity: Alert on suspicious Dataflow profile execution

Impact

An attacker with admin access can read sensitive files including:

• /etc/passwd - System user information
• app/etc/local.xml - Database credentials
• .env files - Environment secrets
• Log files - Potentially sensitive application data
• Configuration files - Server and application configuration

Credit

This vulnerability was discovered and responsibly disclosed by blackhat2013 through HackerOne.

Timeline

• 2025-12-31: Vulnerability reported via HackerOne
• 2026-01-21: Fix developed and tested