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CVE-2026-41661 (GCVE-0-2026-41661)

Vulnerability from cvelistv5 – Published: 2026-05-07 02:59 – Updated: 2026-05-07 14:58
VLAI
Title
Admidio: Reflected XSS in msg_window.php via Square Bracket to HTML Tag Conversion
Summary
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.
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-07 13:55 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
References
Impacted products
Vendor Product Version CPE status
Admidio admidio Affected: < 5.0.9
guessed Create a notification for this product.
Show details on NVD website

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