CVE-2026-9445: Simple POS Inventory System RCE Flaw

CVE-2026-9445 Overview

CVE-2026-9445 is an unrestricted file upload vulnerability in SourceCodester Simple POS and Inventory System 1.0. The flaw resides in the /admin/addproduct.php script, within the File Extension Handler component. Attackers can manipulate the image parameter to upload files without server-side extension validation. Remote exploitation is possible over the network and requires low-privilege authentication. A public proof-of-concept has been published, increasing the likelihood of opportunistic abuse. The weakness is classified under CWE-284: Improper Access Control.

Critical Impact

Authenticated remote attackers can upload arbitrary files through the product image parameter, potentially leading to web shell deployment and further compromise of the hosting environment.

Affected Products

• SourceCodester Simple POS and Inventory System 1.0
• /admin/addproduct.php File Extension Handler component
• Deployments exposing the admin interface over the network

Discovery Timeline

• 2026-05-25 - CVE-2026-9445 published to the National Vulnerability Database (NVD)
• 2026-05-26 - Last updated in NVD database

Technical Details for CVE-2026-9445

Vulnerability Analysis

The vulnerability stems from improper access control over file uploads handled by /admin/addproduct.php. The script accepts a file submitted through the image argument but fails to enforce restrictions on file type, extension, or content. An authenticated user with low-privilege access to the admin panel can submit a file whose extension or MIME type would normally be rejected by a hardened upload handler.

Because the application stores the uploaded artifact within the web root, attackers can request the file via HTTP after upload. If the server interprets the uploaded file as executable script content, the attacker gains code execution in the context of the web server process. This enables web shell installation, lateral access to the underlying database, and theft of inventory or customer records.

The public exploit reported via VulDB Vulnerability #365426 demonstrates the upload path. EPSS data places the probability of exploitation in the wild at the low end of the distribution, but the public proof-of-concept lowers the skill barrier for opportunistic attackers.

Root Cause

The root cause is missing server-side validation of uploaded files in the File Extension Handler. The handler trusts client-supplied metadata for the image field and does not enforce an allow-list of safe extensions, MIME types, or magic bytes. Coupled with predictable upload paths under the web root, this turns a routine product image upload into an arbitrary file write primitive.

Attack Vector

An attacker authenticates to the admin interface with any valid low-privilege account. The attacker then submits a multipart POST request to /admin/addproduct.php containing a malicious file in the image parameter, such as a PHP script renamed with an image extension or sent with a manipulated Content-Type. After the upload completes, the attacker requests the stored file directly to trigger execution. See the public proof-of-concept gist for the exact request structure.

// No verified exploit code is reproduced here.
// Refer to the linked GitHub Gist PoC and VulDB entry
// for the request structure and parameter manipulation details.

Detection Methods for CVE-2026-9445

Indicators of Compromise

• Unexpected files with executable extensions such as .php, .phtml, or .phar inside the product image upload directory of Simple POS and Inventory System
• POST requests to /admin/addproduct.php containing multipart payloads where the image field carries non-image content or mismatched magic bytes
• HTTP GET requests directly targeting newly created files inside the upload directory shortly after a product creation event

Detection Strategies

• Monitor web server access logs for sequences of POST requests to /admin/addproduct.php followed by GET requests to files within the upload directory
• Inspect uploaded files by comparing declared extensions and MIME types against actual file signatures using server-side scanning
• Alert on creation of script-executable files within directories that should contain only static media

Monitoring Recommendations

• Forward web server, PHP-FPM, and file integrity monitoring logs to a centralized analytics platform for correlation
• Track authentication events for admin accounts and correlate them with upload activity to surface compromised or abused credentials
• Baseline normal product image upload volume and alert on deviations indicative of automated abuse

How to Mitigate CVE-2026-9445

Immediate Actions Required

• Restrict network access to the /admin/ path of Simple POS and Inventory System to trusted management IP ranges
• Audit the product image upload directory for unknown script files and remove any unauthorized artifacts
• Rotate credentials for all admin accounts and review recent login activity for anomalies

Patch Information

No vendor patch has been published for SourceCodester Simple POS and Inventory System 1.0 at the time of NVD publication. Consult the SourceCodester project page and the VulDB advisory for any subsequent fix releases.

Workarounds

• Configure the web server to disable script execution within the product image upload directory using directives such as php_flag engine off or equivalent location-based rules
• Add a web application firewall rule that rejects multipart uploads to /admin/addproduct.php whose image field does not contain valid image magic bytes
• Enforce an allow-list of permitted extensions (.jpg, .jpeg, .png, .gif) at the reverse proxy or WAF layer until a vendor fix is available

# Example Apache configuration to block script execution in uploads
<Directory "/var/www/simple-pos/uploads">
    php_flag engine off
    AddHandler default-handler .php .phtml .phar .php3 .php4 .php5 .php7
    Options -ExecCGI
</Directory>