What is CVE-2025-63828?

CVE-2025-63828 is a medium-severity vulnerability in Backdropcms Backdrop Cms, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.1/10. Published 2025-11-18.

How severe is CVE-2025-63828?

Medium severity. CVSS v3 base score is 6.1 out of 10.

Open Redirect in Backdropcms Backdrop Cms

CVE-2025-63828

Host Header Injection vulnerability in Backdrop CMS 1.32.1 allows attackers to manipulate the Host header in password reset requests, leading to redirects to malicious domains and potential session hijacking via cookie injection.

Vulnerability class: Open Redirect

Published 2025-11-18 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (13.7th percentile), scored 2026-10-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Backdropcms Backdrop Cms — versions 1.32.1

Weakness classification (CWE)

CWE-601 — URL Redirection to Untrusted Site (Open Redirect)

References

github.com/mertdurum06/BackdropCms-1.32.1/ (Release Notes)
github.com/mertdurum06/BackdropCms-1.32.1/blob/main/backdropcms_exploit.txt (Exploit)

Frequently asked questions

What is CVE-2025-63828?: CVE-2025-63828 is a medium-severity vulnerability in Backdropcms Backdrop Cms, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.1/10. Published 2025-11-18.
How severe is CVE-2025-63828?: Medium severity. CVSS v3 base score is 6.1 out of 10.