diff --git a/src/fido/cbor_get_info.c b/src/fido/cbor_get_info.c
index 443c511..8812376 100644
--- a/src/fido/cbor_get_info.c
+++ b/src/fido/cbor_get_info.c
@@ -90,7 +90,7 @@ int cbor_get_info() {
     CBOR_CHECK(cbor_encode_uint(&mapEncoder, MAX_CRED_ID_LENGTH)); // MAX_CRED_ID_MAX_LENGTH
 
     CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x0A));
-    CBOR_CHECK(cbor_encoder_create_array(&mapEncoder, &arrayEncoder, 3));
+    CBOR_CHECK(cbor_encoder_create_array(&mapEncoder, &arrayEncoder, 4));
     CBOR_CHECK(cbor_encoder_create_map(&arrayEncoder, &mapEncoder2, 2));
     CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "alg"));
     CBOR_CHECK(cbor_encode_negative_int(&mapEncoder2, -FIDO2_ALG_ES256));
@@ -109,6 +109,12 @@ int cbor_get_info() {
     CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "type"));
     CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "public-key"));
     CBOR_CHECK(cbor_encoder_close_container(&arrayEncoder, &mapEncoder2));
+    CBOR_CHECK(cbor_encoder_create_map(&arrayEncoder, &mapEncoder2, 2));
+    CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "alg"));
+    CBOR_CHECK(cbor_encode_negative_int(&mapEncoder2, -FIDO2_ALG_ES256K));
+    CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "type"));
+    CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "public-key"));
+    CBOR_CHECK(cbor_encoder_close_container(&arrayEncoder, &mapEncoder2));
     CBOR_CHECK(cbor_encoder_close_container(&mapEncoder, &arrayEncoder));
 
     CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x0B));
diff --git a/src/fido/cbor_make_credential.c b/src/fido/cbor_make_credential.c
index 987f768..c630dcf 100644
--- a/src/fido/cbor_make_credential.c
+++ b/src/fido/cbor_make_credential.c
@@ -177,6 +177,9 @@ int cbor_make_credential(const uint8_t *data, size_t len) {
         else if (pubKeyCredParams[i].alg == FIDO2_ALG_ES512) {
             curve = FIDO2_CURVE_P521;
         }
+        else if (pubKeyCredParams[i].alg == FIDO2_ALG_ES256K) {
+            curve = FIDO2_CURVE_P256K1;
+        }
         else if (pubKeyCredParams[i].alg == 0) { // no present
             curve = -1;
         }
diff --git a/src/fido/fido.h b/src/fido/fido.h
index a063daf..06d547b 100644
--- a/src/fido/fido.h
+++ b/src/fido/fido.h
@@ -64,6 +64,7 @@ extern int ecdh(uint8_t protocol, const mbedtls_ecp_point *Q, uint8_t *sharedSec
 #define FIDO2_ALG_ES384     -35 //ECDSA-SHA384 P384
 #define FIDO2_ALG_ES512     -36 //ECDSA-SHA512 P521
 #define FIDO2_ALG_ECDH_ES_HKDF_256 -25 //ECDH-ES + HKDF-256
+#define FIDO2_ALG_ES256K    -47
 
 #define FIDO2_CURVE_P256        1
 #define FIDO2_CURVE_P384        2