4.8
MEDIUM CVSS 4.0
CVE-2026-25133
October CMS has Stored XSS via SVG Filter Bypass
Description

October is a Content Management System (CMS) and web platform. Versions prior to 3.7.14 and 4.1.10 contain a stored cross-site scripting (XSS) vulnerability in the SVG sanitization logic. The regex pattern used to strip event handler attributes (such as onclick or onload) could be bypassed using a crafted payload that exploits how the pattern matches attribute boundaries, allowing malicious SVG files to be uploaded through the Media Manager with embedded JavaScript. Exploitation could lead to privilege escalation if a superuser views or embeds the malicious SVG, and requires authenticated backend access with media upload permissions. The SVG must be viewed or embedded in a page for the payload to trigger. This issue has been fixed in versions 3.7.14 and 4.1.10.

INFO

Published Date :

April 14, 2026, 9:16 p.m.

Last Modified :

April 14, 2026, 9:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-25133 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM [email protected]
Solution
Update October CMS to version 3.7.14 or 4.1.10 to fix SVG sanitization XSS vulnerability.
  • Update October CMS to version 3.7.14.
  • Update October CMS to version 4.1.10.
  • Review uploaded SVG files for malicious content.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-25133.

URL Resource
https://github.com/octobercms/october/security/advisories/GHSA-gcqv-f29m-67gr
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-25133 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-25133 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-25133 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-25133 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Apr. 14, 2026

    Action Type Old Value New Value
    Added Description October is a Content Management System (CMS) and web platform. Versions prior to 3.7.14 and 4.1.10 contain a stored cross-site scripting (XSS) vulnerability in the SVG sanitization logic. The regex pattern used to strip event handler attributes (such as onclick or onload) could be bypassed using a crafted payload that exploits how the pattern matches attribute boundaries, allowing malicious SVG files to be uploaded through the Media Manager with embedded JavaScript. Exploitation could lead to privilege escalation if a superuser views or embeds the malicious SVG, and requires authenticated backend access with media upload permissions. The SVG must be viewed or embedded in a page for the payload to trigger. This issue has been fixed in versions 3.7.14 and 4.1.10.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-79
    Added Reference https://github.com/octobercms/october/security/advisories/GHSA-gcqv-f29m-67gr
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.