LOW

GHSA-gjwq-9v8p-47w7

Concrete CMS's RSS Displayer block accepts a feed URL from any page editor and fetches it server-side without validation

Quick fix

GHSA-gjwq-9v8p-47w7 — concrete5/concrete5: upgrade to the fixed version with the command below.

composer require concrete5/concrete5:^9.5.1

Details

In Concrete CMS 9.5.0 and below, the RSS Displayer block accepts a feed URL from any page editor and fetches it server-side without validation enabling redirect-to-internal bypasses.

Are you affected?

Enter the version of the package you're using.

Affected packages

Packagist/concrete5/concrete5

Introduced in: 0Fixed in: 9.5.1

Fixcomposer require concrete5/concrete5:^9.5.1

References

https://nvd.nist.gov/vuln/detail/CVE-2026-7890[ADVISORY]
https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes[WEB]
https://github.com/concretecms/concretecms[PACKAGE]