CVE-2026-25133

MEDIUM

October CMS has Stored XSS via SVG Filter Bypass

Title source: cna
STIX 2.1

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.

References (1)

Core 1
Core References

Scores

CVSS v3 4.8
EPSS 0.0022
EPSS Percentile 11.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-79
Status published
Products (5)
october/rain 0 - 3.7.14Packagist
october/rain 4.0.0 - 4.1.10Packagist
octobercms/october < 3.7.13
octobercms/october < 3.7.14
octobercms/october >= 4.0.0, < 4.1.10
Published Apr 14, 2026
Tracked Since Apr 15, 2026