diff --git a/src/fido/cbor_cred_mgmt.c b/src/fido/cbor_cred_mgmt.c
index 2054df5..07dc6e3 100644
--- a/src/fido/cbor_cred_mgmt.c
+++ b/src/fido/cbor_cred_mgmt.c
@@ -302,6 +302,7 @@ int cbor_cred_mgmt(const uint8_t *data, size_t len) {
                 }
                 CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x0B));
                 CBOR_CHECK(cbor_encode_byte_string(&mapEncoder, largeBlobKey, sizeof(largeBlobKey)));
+                mbedtls_platform_zeroize(largeBlobKey, sizeof(largeBlobKey));
             }
         }
         credential_free(&cred);