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.
Weakness
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
Related Attack Patterns
References
- https://github.com/0xGenesi/CVE/blob/main/October_CMS_SSRF_IPv6_Mapped_IPv4_Bypass.md
- https://github.com/octobercms/october/releases/tag/v4.3.5
- https://github.com/octobercms/october/security/advisories/GHSA-j2j7-7m99-6226
- https://vuldb.com/cve/CVE-2026-101005
- https://vuldb.com/submit/922294
- https://vuldb.com/vuln/410875
- https://vuldb.com/vuln/410875/cti
- https://www.cybersecurity-help.cz/vdb/vulns/149488/