CVE-2026-7129: Pharmacy Sales Inventory System XSS Flaw

CVE-2026-7129 Overview

A cross-site scripting (XSS) vulnerability has been identified in SourceCodester Pharmacy Sales and Inventory System version 1.0. The vulnerability exists in the /index.php?page=categories endpoint, where improper handling of the ID parameter allows attackers to inject malicious scripts. This reflected XSS vulnerability can be exploited remotely without authentication, though it requires user interaction to trigger.

Critical Impact
Attackers can inject malicious JavaScript code that executes in the context of a victim's browser session, potentially leading to session hijacking, credential theft, or unauthorized actions within the pharmacy management system.

Affected Products

SourceCodester Pharmacy Sales and Inventory System 1.0

Discovery Timeline

2026-04-27 - CVE-2026-7129 published to NVD
2026-04-29 - Last updated in NVD database

Technical Details for CVE-2026-7129

Vulnerability Analysis

This vulnerability is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation), commonly known as Cross-Site Scripting. The vulnerable endpoint /index.php?page=categories accepts user-controlled input through the ID parameter without proper sanitization or encoding before reflecting it back in the HTTP response.

When a user clicks a malicious link containing crafted JavaScript in the ID parameter, the script executes within their authenticated browser session. This is particularly concerning in a pharmacy sales and inventory management context, where sensitive patient data, medication records, and financial information may be accessible.

The exploit has been publicly disclosed, increasing the risk of exploitation in the wild. Organizations running this software should treat remediation as a priority despite the low severity rating.

Root Cause

The root cause of this vulnerability is the lack of input validation and output encoding in the category handling functionality. The ID parameter value is directly incorporated into the page output without sanitization, allowing HTML and JavaScript injection. The application fails to implement proper escaping mechanisms such as HTML entity encoding or Content Security Policy headers that would prevent script execution.

Attack Vector

The attack is network-based and can be executed remotely. An attacker crafts a malicious URL containing JavaScript code in the ID parameter of the /index.php?page=categories endpoint. The attacker then distributes this URL through phishing emails, social engineering, or by embedding it in compromised websites.

When a victim with an active session in the Pharmacy Sales and Inventory System clicks the malicious link, the injected JavaScript executes in their browser context. This can lead to:

Session cookie theft enabling account takeover
Keylogging of sensitive data entered on the page
Modification of displayed content (DOM manipulation)
Redirection to malicious websites
Unauthorized actions performed on behalf of the authenticated user

For technical details regarding the vulnerability mechanism, refer to the GitHub Issue Discussion and VulDB #359728.

Detection Methods for CVE-2026-7129

Indicators of Compromise

Web server access logs showing requests to /index.php?page=categories with suspicious ID parameter values containing <script>, javascript:, onerror=, or other XSS payloads
Unusual encoded characters in URL parameters such as %3Cscript%3E or HTML entity-encoded strings
User reports of unexpected behavior, pop-ups, or redirections when accessing the categories page
Session tokens appearing in third-party server logs indicating potential exfiltration

Detection Strategies

Deploy Web Application Firewall (WAF) rules to detect and block common XSS patterns in the ID parameter
Implement Content Security Policy (CSP) headers and monitor for CSP violation reports
Configure intrusion detection systems to alert on suspicious JavaScript patterns in HTTP requests
Review application logs for anomalous requests to the /index.php?page=categories endpoint

Monitoring Recommendations

Enable detailed logging for all requests to the vulnerable endpoint and establish baseline patterns
Monitor for spikes in access to the categories functionality from unusual geographic locations or IP addresses
Track referrer headers for links pointing to the application with suspicious query parameters
Implement real-time alerting for requests containing common XSS payloads or encoding patterns

How to Mitigate CVE-2026-7129

Immediate Actions Required

Contact SourceCodester for any available security patches or updated versions
Implement input validation to restrict the ID parameter to expected numeric values only
Apply output encoding (HTML entity encoding) for all user-supplied data reflected in responses
Deploy WAF rules to filter XSS payloads targeting the /index.php?page=categories endpoint

Patch Information

No official patch has been confirmed at the time of publication. Organizations should monitor the SourceCodester website for security updates. In the absence of an official patch, implementing the workarounds below is strongly recommended.

Additional vulnerability details are available at VulDB Submission #800974 and VulDB #359728 CTI.

Workarounds

Implement server-side input validation to ensure the ID parameter only accepts numeric values
Apply HTML output encoding using PHP's htmlspecialchars() or htmlentities() functions
Add Content Security Policy headers to prevent inline script execution: Content-Security-Policy: script-src 'self'
Restrict access to the application to trusted networks or implement additional authentication controls
Consider disabling the categories functionality temporarily if not critical to operations

bash

# Apache .htaccess configuration to add CSP headers
<IfModule mod_headers.c>
    Header set Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'"
    Header set X-XSS-Protection "1; mode=block"
    Header set X-Content-Type-Options "nosniff"
</IfModule>