CVE-2025-63526: Blood Bank Management System XSS Flaw

CVE-2025-63526 Overview

A cross-site scripting (XSS) vulnerability exists in the Blood Bank Management System within the abs.php component. The application fails to properly sanitize or encode user-supplied input before rendering it in response. An attacker can inject malicious JavaScript payloads into the msg parameter, which is then executed in the victim's browser when the page is viewed.

This reflected XSS vulnerability allows attackers to execute arbitrary JavaScript code in the context of a victim's browser session, potentially leading to session hijacking, credential theft, or further exploitation of authenticated users.

Critical Impact

Attackers can inject malicious JavaScript via the msg parameter in abs.php, enabling session hijacking, cookie theft, and unauthorized actions on behalf of authenticated users within the Blood Bank Management System.

Affected Products

• Shridharshukl Blood Bank Management System version 1.0
• abs.php component with vulnerable msg parameter handling
• All deployments using unpatched versions of the application

Discovery Timeline

• 2025-12-01 - CVE-2025-63526 published to NVD
• 2025-12-02 - Last updated in NVD database

Technical Details for CVE-2025-63526

Vulnerability Analysis

This vulnerability is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation), commonly known as Cross-Site Scripting (XSS). The vulnerability carries a CVSS v3.1 score of 5.4 (Medium) with the vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

The CVSS metrics indicate:

• Attack Vector (AV:N): Network-based exploitation is possible
• Attack Complexity (AC:L): Low complexity required for exploitation
• Privileges Required (PR:L): Low-level privileges needed
• User Interaction (UI:R): Requires user interaction (victim must visit malicious link)
• Scope (S:C): Changed scope - can affect components beyond the vulnerable component
• Confidentiality Impact (C:L): Low impact on confidentiality
• Integrity Impact (I:L): Low impact on integrity
• Availability Impact (A:N): No impact on availability

The Exploit Prediction Scoring System (EPSS) indicates a probability of 0.031% with a percentile ranking of 8.437, suggesting relatively low likelihood of exploitation in the wild.

Root Cause

The root cause of this vulnerability lies in the improper handling of user-supplied input within the abs.php component. The application directly incorporates the msg parameter value into the HTML response without proper sanitization, encoding, or validation. This failure to implement output encoding allows malicious script content to be rendered as executable code rather than being treated as plain text.

The vulnerability specifically stems from:

• Missing input validation on the msg parameter
• Absence of HTML entity encoding before rendering user input
• Lack of Content Security Policy (CSP) headers to mitigate XSS impact

Attack Vector

The attack vector is network-based, requiring an attacker to craft a malicious URL containing JavaScript payload in the msg parameter. The attacker must then convince a victim to click on the malicious link, typically through social engineering tactics such as phishing emails or malicious website redirects.

When the victim visits the crafted URL while authenticated to the Blood Bank Management System, the malicious JavaScript executes within their browser session. This allows the attacker to:

• Steal session cookies and authentication tokens
• Perform actions on behalf of the authenticated user
• Redirect users to malicious websites
• Capture sensitive data entered on the page
• Modify page content to display misleading information

The vulnerability is documented in external exploit references available at the GitHub repository CVE-2025-63526.md.

Detection Methods for CVE-2025-63526

Indicators of Compromise

• Suspicious HTTP requests to abs.php containing <script> tags or JavaScript event handlers in the msg parameter
• URL-encoded JavaScript payloads such as %3Cscript%3E in request logs targeting the abs.php endpoint
• Unusual patterns in web server access logs showing attempts to inject javascript:, onerror=, onload=, or similar XSS vectors
• Reports from users about unexpected browser behavior or redirects when accessing the Blood Bank Management System

Detection Strategies

Organizations can implement the following detection strategies to identify exploitation attempts:

1. Web Application Firewall (WAF) Rules: Configure WAF rules to detect and block common XSS patterns in the msg parameter, including <script>, event handlers, and encoded variations.

2. Log Analysis: Monitor web server logs for requests to abs.php containing suspicious characters or patterns indicative of XSS attempts.

3. Intrusion Detection Systems (IDS): Deploy signatures that detect XSS payload patterns in HTTP traffic destined for the Blood Bank Management System.

4. Browser Security Headers Monitoring: Verify that Content Security Policy headers are properly configured and monitor for CSP violation reports.

Monitoring Recommendations

• Enable detailed logging for all requests to the abs.php component
• Implement real-time alerting for requests containing script tags or JavaScript event handlers
• Monitor for anomalous user session behavior that might indicate successful XSS exploitation
• Review authentication logs for suspicious activity following potential XSS attack attempts
• Deploy endpoint detection and response (EDR) solutions to detect browser-based attacks

How to Mitigate CVE-2025-63526

Immediate Actions Required

• Implement input validation and output encoding for the msg parameter in abs.php
• Deploy Content Security Policy (CSP) headers to restrict script execution sources
• Configure Web Application Firewall rules to block XSS attack patterns
• Review and restrict access to the Blood Bank Management System to trusted networks if possible
• Educate users about the risks of clicking on suspicious links

Patch Information

As of the last NVD update on 2025-12-02, no official vendor patch has been announced for this vulnerability. Organizations using the Shridharshukl Blood Bank Management System should:

• Monitor the official GitHub repository at https://github.com/Shridharshukl/Blood-Bank-Management-System for security updates
• Consider implementing manual code fixes to sanitize the msg parameter
• Evaluate alternative blood bank management solutions if no patch is forthcoming

Workarounds

In the absence of an official patch, organizations can implement the following workarounds to mitigate the risk:

The primary mitigation involves implementing proper output encoding for all user-supplied input. PHP applications should use htmlspecialchars() or equivalent functions to encode special characters before rendering them in HTML output.

# Recommended sanitization for the msg parameter
$msg = htmlspecialchars($_GET['msg'], ENT_QUOTES, 'UTF-8');

Additional defensive measures include implementing Content Security Policy headers to restrict script execution:

# Apache .htaccess configuration for CSP
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'"

Organizations should also consider placing the application behind a reverse proxy with XSS filtering capabilities and restricting access to authenticated and authorized users only.