An unauthenticated user who has write access to the knowledge base can embed an XSS payload in a knowledge base item. The vulnerability allows the payload to be stored and later executed in the browsers of any user who views the item, potentially enabling cookie theft, account hijacking, or phishing attacks. The weakness matches CWE‑79, focused on improper input validation that leads to client‑side script injection.

The issue affects all GLPI Product releases prior to version 11.0.7. Users running any older GLPI build should identify whether they are on an unsupported release and determine if they have any write access to the knowledge base module.

The CVSS score of 8.4 classifies the flaw as high severity. The EPSS score is not available, and the vulnerability is not listed in CISA KEV. The attack vector requires the attacker to obtain write permission on the knowledge base—an unauthenticated user with such rights can inject the malicious content. Once injected, all users who view the knowledge base item are exposed to the client‑side code, making this a significant risk for organizations using GLPI without hardened access controls.