October CMS: DataTable फॉर्म विजेट के माध्यम से परावर्तित XSS

The vulnerability lies in the improper output escaping of a query parameter within the backend DataTable widget. Successful exploitation allows an attacker to inject and execute arbitrary JavaScript code within the context of the affected user's session. While the vulnerability is classified as reflected XSS, meaning the payload is not stored persistently, it still poses a significant risk. An attacker could potentially steal session cookies, redirect users to malicious websites, or deface the backend interface. The attack requires an authenticated backend user to visit a specially crafted URL, and the attacker must know or be able to guess the backend URL prefix, which is customizable.

Organizations using October CMS versions 4.0.0 through 4.1.15 are at risk. Specifically, those with custom backend URL prefixes or those who allow user-supplied input to influence the DataTable queries are more vulnerable. Shared hosting environments running October CMS should also be prioritized for patching.

• php: Examine October CMS application logs for unusual URL parameters or JavaScript execution attempts.

grep -i 'javascript:' /path/to/october/cms/logs/error.log

• generic web: Monitor access logs for requests containing suspicious query parameters in the DataTable URL.

curl -I https://your-october-cms-site.com/backend/october/manage/settings/datatables?param=javascript:alert('XSS')

• generic web: Check response headers for signs of JavaScript injection.

curl -I https://your-october-cms-site.com/backend/october/manage/settings/datatables?param=javascript:alert('XSS') | grep Content-Type

1. 2026-04-21Disclosure

   disclosure

1. आरक्षित2026-02-25
2. प्रकाशित2026-04-21
3. EPSS अद्यतन2026-04-29

The primary mitigation for CVE-2026-27937 is to upgrade to a patched version of October CMS. Version 4.1.16 and 3.7.16 contain the necessary fixes to properly escape the vulnerable query parameter. If an immediate upgrade is not feasible, consider implementing a Web Application Firewall (WAF) rule to filter requests containing suspicious query parameters. Additionally, restrict access to the backend interface and enforce strong password policies to minimize the risk of unauthorized access. After upgrading, confirm the fix by attempting to inject a simple JavaScript payload via the vulnerable query parameter and verifying that it is properly sanitized.