CVE-2024-23861: Cups Easy Purchase & Inventory XSS Flaw

CVE-2024-23861 Overview

CVE-2024-23861 is a reflected Cross-Site Scripting (XSS) vulnerability [CWE-79] in Ajaysharma Cups Easy (Purchase & Inventory) version 1.0. The application fails to sufficiently encode user-controlled input passed through the unitofmeasurementid parameter of /cupseasylive/unitofmeasurementcreate.php. An attacker can craft a malicious URL that, when opened by an authenticated user, executes arbitrary JavaScript in the victim's browser context. Successful exploitation allows theft of session cookies and impersonation of the authenticated user within the Cups Easy application.

Critical Impact
Remote attackers can hijack authenticated sessions and perform actions on behalf of victim users by delivering a crafted URL.

Affected Products

Ajaysharma Cups Easy (Purchase & Inventory) version 1.0
CPE: cpe:2.3:a:ajaysharma:cups_easy:1.0
Endpoint: /cupseasylive/unitofmeasurementcreate.php

Discovery Timeline

2024-01-26 - CVE-2024-23861 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-23861

Vulnerability Analysis

The vulnerability resides in the unitofmeasurementcreate.php script within the /cupseasylive/ path. The script accepts the unitofmeasurementid request parameter and reflects its value back into the HTTP response without applying output encoding or input sanitization. Because the reflected content is rendered in an HTML context, an attacker can inject script tags or event handlers that the browser then executes.

Exploitation requires user interaction. The attacker must deliver the crafted URL to an authenticated Cups Easy user through phishing, chat, or another delivery channel. When the victim visits the link, the injected payload runs with the origin of the vulnerable application. This enables session cookie theft, forced actions inside the application, and pivoting to other application functions accessible to the victim.

Root Cause

The root cause is missing output encoding of user-supplied input rendered into an HTML response, mapped to [CWE-79] (Improper Neutralization of Input During Web Page Generation). The unitofmeasurementid parameter is placed into the DOM without HTML entity encoding or contextual escaping.

Attack Vector

The attack vector is network-based and requires user interaction. An unauthenticated remote attacker crafts a URL targeting the unitofmeasurementcreate.php endpoint with a malicious payload in the unitofmeasurementid parameter. The victim must be an authenticated Cups Easy user and must click the link for the payload to execute. Scope changes because scripts execute in the victim's browser under the application origin, allowing access to session cookies unless they are protected with HttpOnly.

Detailed technical information is available in the INCIBE Notice on CUPS Vulnerabilities.

Detection Methods for CVE-2024-23861

Indicators of Compromise

HTTP requests to /cupseasylive/unitofmeasurementcreate.php containing <script>, onerror=, onload=, or URL-encoded equivalents in the unitofmeasurementid parameter.
Referer headers from external domains linking to unitofmeasurementcreate.php with query strings.
Unusual outbound requests from user browsers to attacker-controlled domains immediately after visiting Cups Easy URLs.

Detection Strategies

Inspect web server access logs for suspicious payloads in the unitofmeasurementid GET parameter.
Deploy Web Application Firewall (WAF) signatures that flag script tags, JavaScript URIs, and event handlers in query parameters.
Correlate authentication events with anomalous session activity, such as new IP addresses reusing existing session cookies.

Monitoring Recommendations

Enable full HTTP request logging on the Cups Easy web server, including query strings and Referer headers.
Forward web logs to a centralized analytics platform for pattern matching on reflected XSS payloads.
Alert on outbound connections from internal workstations to unknown domains following access to Cups Easy.

How to Mitigate CVE-2024-23861

Immediate Actions Required

Restrict access to the Cups Easy application to trusted internal networks until a patched version is deployed.
Instruct users to avoid clicking untrusted links referencing /cupseasylive/unitofmeasurementcreate.php.
Set the HttpOnly and Secure flags on session cookies to reduce the impact of cookie theft via JavaScript.

Patch Information

No vendor patch or fixed version is referenced in the NVD entry for CVE-2024-23861. Consult the INCIBE Notice on CUPS Vulnerabilities for the latest vendor guidance and monitor the Ajaysharma Cups Easy repository for updates.

Workarounds

Deploy a WAF rule that rejects requests to /cupseasylive/unitofmeasurementcreate.php when the unitofmeasurementid parameter contains HTML metacharacters such as <, >, ", or '.
Enforce a strict Content Security Policy (CSP) that disallows inline scripts and restricts script sources to trusted origins.
Apply server-side input validation to constrain unitofmeasurementid to expected numeric values before rendering.

bash

# Example ModSecurity rule to block suspicious payloads in the vulnerable parameter
SecRule ARGS:unitofmeasurementid "@rx (?i)(<script|onerror=|onload=|javascript:)" \
    "id:1002024,phase:2,deny,status:403,log,msg:'CVE-2024-23861 XSS attempt blocked'"