CVE-2026-81913

Concrete CMS versions 9.5.0 through 9.5.2 are vulnerable to Open Redirect via the rcURL parameter. An attacker can craft a single link on the site's own domain that sends a user to an arbitrary external site immediately after authentication, facilitating phishing and credential theft. The same handling is present in the registration flow, giving a second entry point on sites with registration enabled. Concrete CMS versions prior to 9.5.0 do not include the rcURL parameter or this allowlist and are not affected. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 5.3 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Michal M. for reporting.

CVSS

No CVSS.

References

Link	Resource
https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 20:19

Updated : 2026-09-15 14:40

NVD link : CVE-2026-81913

Mitre link : CVE-2026-81913

CVE.ORG link : CVE-2026-81913

JSON object : View

Products Affected

No product.

CWE

CWE-601

URL Redirection to Untrusted Site ('Open Redirect')

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