An attacker with local access the to medical office computer can escalate his Windows user privileges to "NT AUTHORITY\SYSTEM" by exploiting a race condition in the Elefant Update Service during the repair or update process. When using the repair function, the service queries the server for a list of files and their hashes. In addition, instructions to execute binaries to finalize the repair process are included. The executables are executed as "NT AUTHORITY\SYSTEM" after they are copied over to the user writable installation folder (C:\Elefant1). This means that a user can overwrite either "PostESUUpdate.exe" or "Update_OpenJava.exe" in the time frame after the copy and before the execution of the final repair step. The overwritten executable is then executed as "NT AUTHORITY\SYSTEM".
| Métrique | Valeur | Interprétation |
|---|---|---|
|
AV (Vecteur d'Attaque)
Attack Vector
|
Local (L)
|
Exploit nécessite un accès local au système |
|
AC (Complexité d'Attaque)
Attack Complexity
|
High (H)
|
Conditions spécifiques doivent être réunies pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
Low (L)
|
Authentifié avec compte utilisateur basique |
|
UI (Interaction Utilisateur)
User Interaction
|
None (N)
|
Aucune interaction utilisateur nécessaire |
|
S (Périmètre)
Scope
|
Unchanged (U)
|
Impact reste dans le périmètre du composant compromis |
|
C (Impact Confidentialité)
Confidentiality Impact
|
High (H)
|
Divulgation totale d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
High (H)
|
Modification totale des données possible |
|
A (Impact Disponibilité)
Availability Impact
|
High (H)
|
Interruption totale du service possible |