---
id: CVE-2026-101005
title: A vulnerability was detected in October CMS up to 4.3.4
summary: >-
  A vulnerability was detected in October CMS up to 4.3.4. This affects the
  function validateExternalImageHost of the file System/Classes/ResizeImages.php
  of the component SSRF Protection. The manipulation results in server-side
  request fo…
severity: high
cvss: 7.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L'
cwe:
  - CWE-918
product: October CMS
affected:
  - october_cms 4.3.0
  - october_cms 4.3.1
  - october_cms 4.3.2
  - october_cms 4.3.3
  - october_cms 4.3.4
published: '2026-09-28'
updated: '2026-09-28'
sourceUpdated: '2026-09-28T07:17:19.827'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-101005'
references:
  - url: >-
      https://github.com/0xGenesi/CVE/blob/main/October_CMS_SSRF_IPv6_Mapped_IPv4_Bypass.md
    label: cna@vuldb.com
  - url: 'https://github.com/octobercms/october/releases/tag/v4.3.5'
    label: cna@vuldb.com
  - url: >-
      https://github.com/octobercms/october/security/advisories/GHSA-j2j7-7m99-6226
    label: cna@vuldb.com
  - url: 'https://vuldb.com/cve/CVE-2026-101005'
    label: cna@vuldb.com
  - url: 'https://vuldb.com/submit/922294'
    label: cna@vuldb.com
  - url: 'https://vuldb.com/vuln/410875'
    label: cna@vuldb.com
  - url: 'https://vuldb.com/vuln/410875/cti'
    label: cna@vuldb.com
  - url: 'https://www.cybersecurity-help.cz/vdb/vulns/149488/'
    label: cna@vuldb.com
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-28T07:04:53.496Z'
---

## Overview

A vulnerability was detected in October CMS up to 4.3.4. This affects the function validateExternalImageHost of the file System/Classes/ResizeImages.php of the component SSRF Protection. The manipulation results in server-side request forgery. The attack may be launched remotely. The exploit is now public and may be used. Upgrading to version 4.3.5 is able to mitigate this issue. You should upgrade the affected component.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.