CVE-2026-25133: October/rain Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-gcqv-f29m-67gr
Share
CVSS 4.8
CWE-79
Published
Advisory Summary

CVE-2026-25133 is a MODERATE (CVSS 4.8) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting October/rain libraries in the Packagist ecosystem. The issue involves october rain has stored xss via svg filter bypass. Remediation is available by upgrading affected packages to version 4.1.10, 3.7.14.

CVE-2026-25133 at a Glance

CVE Identifier CVE-2026-25133
GHSA Identifier GHSA-gcqv-f29m-67gr
Severity MODERATE
CVSS v3.1 Base Score 4.8
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product October/rain
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 4.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required High (PR:H)
User Interaction Required (UI:R)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2026-25133

To remediate this vulnerability, upgrade all affected October/rain dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

october/rain fixed: 4.1.10 
Upgrade october/rain to 4.1.10
october/rain fixed: 3.7.14 
Upgrade october/rain to 3.7.14
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for october/rain

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-25133, inspect your project dependencies for October/rain:

inspect dependencies for october/rain

Analyze the terminal output to locate any version of October/rain in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 4.1.10), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In October/rain, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

A stored cross-site scripting (XSS) vulnerability was identified in the SVG sanitization logic. The regex pattern used to strip `on*` event handler attributes could be bypassed using a crafted payload that exploits how the pattern matches attribute boundaries. ### Impact - Stored XSS via malicious SVG files uploaded through the Media Manager - Could allow privilege escalation if a superuser views or embeds the malicious SVG - Requires authenticated backend access with media upload permissions (`media.library.create`) - SVG must be viewed or embedded in a page to trigger ### Patches The vulnerability has been patched in v3.7.14 and v4.1.10. All users are encouraged to upgrade to the latest patched version. ### Workarounds If upgrading immediately is not possible: - Disable SVG uploads by adding `svg` to the blocked extensions in media configuration - Set `media.clean_vectors` to `true` in configuration (enabled by default) ### References - Reported by Pentest-Tools.com

CVE-2026-25133 Affected October/rain Versions

2 component(s)
Fixed Versions:
4.1.103.7.14
Product / Package Ecosystem Affected Versions Fixed Version
october/rain
 Packagist
≥ 4.0.0
< 4.1.10
4.1.10
october/rain
 Packagist
< 3.7.14
3.7.14

References

GitHub Advisory / Wiki ADVISORY
https://github.com/octobercms/october/security/advisories/GHSA-gcqv-f29m-67gr
NVD — CVE-2026-25133 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-25133
October/rain Source Repository REPOSITORY
https://github.com/octobercms/october

Frequently Asked Questions

What is CVE-2026-25133?
CVE-2026-25133 is a security vulnerability in October/rain involving October Rain has Stored XSS via SVG Filter Bypass under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which October/rain versions are affected?
Affected versions include releases prior to 4.1.10, 3.7.14 across affected packages: october/rain.
What version fixes CVE-2026-25133?
Upgrading to 4.1.10, 3.7.14 (or the latest patched release for your respective branch) resolves the vulnerability.
Is october/rain affected?
Yes, october/rain is affected in releases prior to 4.1.10, 3.7.14. Upgrade your dependency to 4.1.10, 3.7.14 or later.
What is the CVSS score of CVE-2026-25133?
CVE-2026-25133 has a CVSS v3.1 base score of 4.8 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2026-25133?
CVE-2026-25133 is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check Packagist dependencies for CVE-2026-25133?
Run the dependency tree command: 'inspect dependencies for october/rain'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-gcqv-f29m-67gr",
  "modified" : "2026-05-08T20:41:49Z",
  "published" : "2026-04-14T22:29:50Z",
  "aliases" : [ "CVE-2026-25133" ],
  "summary" : "October Rain has Stored XSS via SVG Filter Bypass",
  "details" : "A stored cross-site scripting (XSS) vulnerability was identified in the SVG sanitization logic. The regex pattern used to strip `on*` event handler attributes could be bypassed using a crafted payload that exploits how the pattern matches attribute boundaries.\n\n### Impact\n- Stored XSS via malicious SVG files uploaded through the Media Manager\n- Could allow privilege escalation if a superuser views or embeds the malicious SVG\n- Requires authenticated backend access with media upload permissions (`media.library.create`)\n- SVG must be viewed or embedded in a page to trigger\n\n### Patches\nThe vulnerability has been patched in v3.7.14 and v4.1.10. All users are encouraged to upgrade to the latest patched version.\n\n### Workarounds\nIf upgrading immediately is not possible:\n- Disable SVG uploads by adding `svg` to the blocked extensions in media configuration\n- Set `media.clean_vectors` to `true` in configuration (enabled by default)\n\n### References\n- Reported by Pentest-Tools.com",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "october/rain"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.0.0"
      }, {
        "fixed" : "4.1.10"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 4.1.9"
    }
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "october/rain"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.7.14"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 3.7.13"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/octobercms/october/security/advisories/GHSA-gcqv-f29m-67gr"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-25133"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/octobercms/october"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-14T22:29:50Z",
    "nvd_published_at" : "2026-04-14T21:16:25Z"
  }
}