CVE-2026-117535: REDAXO before 5.21.3 Reflected XSS via opener_link in Media Pool

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-27 · updated 2026-10-27
Weakness: CWE-79

Description

REDAXO before 5.21.3 contains a reflected cross-site scripting vulnerability in the backend media pool detail page, where the opener_link parameter is rendered without HTML escaping. Unauthenticated attackers can lure logged-in backend users with media permissions into clicking a crafted link. The injected script can then read the CSRF token and perform actions with the victim's permissions, including code execution via template or module edits when the victim is an administrator.

Affected products

redaxo core: before 5.21.3 — fixed in 5.21.3

How to fix

Upgrade to a fixed version: redaxo core 5.21.3. Check the vendor advisory for mitigations.

References

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