H3C HDM Family-A verifies the RSA signature of a firmware image against a public key it reads from the mutable file `/conf/public.pem`. That file is writable by an authenticated Redfish client through the `UpdateService.UploadSignKey` action, which stores the uploaded body verbatim after validating only that the multipart filename ends in `.pem`. An administrator, or any account with `firmware-update` privilege, can therefore replace the trust anchor with their own key, sign a malicious image with the matching private key, and have it pass verification. Family-A has no hardware root-of-trust (no PFR) to catch the substituted key. This was observed on H3C HDM Family-A G5 HDM 6.14.01. H3C HDM Family-A G3/G5 builds carrying the Redfish/DRE update tree appear to be affected. HDM2 uses a different update path and is not covered by this finding.
| 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
|
High (H)
|
Conditions spécifiques doivent être réunies pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
High (H)
|
Authentifié avec privilèges administratifs |
|
UI (Interaction Utilisateur)
User Interaction
|
Required (R)
|
NĂ©cessite une action utilisateur (clic lien, ouverture fichier, etc.) |
|
S (Périmètre)
Scope
|
Unchanged (U)
|
Impact reste dans le périmètre 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 |