Method and system for updating certificate issuer public key, and related device

A terminal, comprising:

• an embedded universal integrated circuit card (eUICC);
• and
• a local profile assistant (LPA) coupled to the eUICC and configured to:
• send first eUICC information to a subscription manager-data preparation (SM-DP+) server, wherein the first eUICC information comprises a verification certificate issuer (CI) public key identifier list of the eUICC;
• receive first information from the SM-DP+ server, wherein the first information comprises a first CI public key identifier, wherein the first CI public key identifier is a CI public key identifier that is stored on the SM-DP+ server and that does not match any CI public key identifier in the verification CI public key identifier list, and the first CI public key identifier is for bidirectional authentication between the SM-DP+ server and the eUICC;
• and
• send the first information to the eUICC,
• wherein the eUICC is configured to:
• receive the first information from the LPA;
• send second information to an operating system patch server (OPS) via the LPA, wherein the second information comprises the first CI public key identifier;
• receive a patch package from the OPS via the LPA, wherein the patch package comprises a first CI public key corresponding to the first CI public key identifier;
• and
• update a CI public key of the eUICC using the first CI public key.