CVE-2026-7890: Concrete CMS's RSS Displayer block accepts a feed URL from any page editor and fetches it server-side without validation

low Affects concrete5/concrete5. Feed 2026.10.29.1, updated 2026-10-28; published 2026-05-22; advisory modified 2026-09-10.

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

Package: concrete5/concrete5 Composer
Affected versions: <9.5.1
Fixed in: 9.5.1
Severity: low
Exploitation: not on CISA KEV · EPSS 0% (4.4th percentile)
Published: 2026-05-22
Source: osv.dev

References

CWE-918

NVD record concrete5/concrete5 advisories

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