VulnerabilityDeferred

CVE-2026-41661

Prior to version 5.0.9, an unauthenticated attacker can execute arbitrary JavaScript in any Admidio user's browser through a reflected XSS in system/msg_window.php.

MEDIUM 6.1EPSS 0.18%

Does this matter?

Lower severity and a low EPSS score (0.18%). Track it; it rarely justifies an emergency change on its own.

Description

Admidio is an open-source user management solution. Prior to version 5.0.9, an unauthenticated attacker can execute arbitrary JavaScript in any Admidio user's browser through a reflected XSS in system/msg_window.php. The endpoint passes user input through htmlspecialchars(), which does not encode square brackets. A subsequent call to Language::prepareTextPlaceholders() converts those brackets into HTML angle brackets, producing executable markup. This issue has been patched in version 5.0.9.

CVSS 3.1: 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS: 0.18% probability · 8th percentile
CISA KEV: Not listed
Weakness: CWE-79
Source: security-advisories@github.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.