iNiLabs School Express (SMS Express) 6.2 is affected by a Stored Cross-Site Scripting (XSS) vulnerability in the content-management features available to authenticated admin users. The vulnerability resides in POSTed editor parameters submitted to the /posts/edit/{id} endpoint (and similarly in Notice and Pages editors). Due to insufficient input sanitization and output encoding, attackers can inject HTML/JS payloads. The payload is saved and later rendered unsanitized, resulting in JavaScript execution in other users' browsers when they access the affected content. This issue allows an authenticated attacker to execute arbitrary JavaScript in the context of another user, potentially leading to session hijacking, privilege escalation, data exfiltration, or administrative account takeover. The application does not enforce a restrictive Content Security Policy (CSP) or adequate filtering to prevent such attacks.
| Métrique | Valeur | Interprétation |
|---|---|---|
|
AV (Vecteur d'Attaque)
Attack Vector
|
Network (N)
|
Exploit possible à distance via réseau (HTTP, API, etc.) |
|
AC (Complexité d'Attaque)
Attack Complexity
|
Low (L)
|
Peu de conditions requises pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
Low (L)
|
Authentifié avec compte utilisateur basique |
|
UI (Interaction Utilisateur)
User Interaction
|
Required (R)
|
Nécessite une action utilisateur (clic lien, ouverture fichier, etc.) |
|
S (Périmètre)
Scope
|
Changed (C)
|
Impact s'étend au-delà du composant compromis |
|
C (Impact Confidentialité)
Confidentiality Impact
|
Low (L)
|
Divulgation limitée d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
Low (L)
|
Modification limitée des données possible |
|
A (Impact Disponibilité)
Availability Impact
|
None (N)
|
Aucune interruption de service |