diff --git a/src/pkcs11/misc.c b/src/pkcs11/misc.c
index cbe66b4b..dd36d951 100644
--- a/src/pkcs11/misc.c
+++ b/src/pkcs11/misc.c
@@ -233,7 +233,7 @@ CK_RV attr_extract(CK_ATTRIBUTE_PTR pAttr, void *ptr, size_t *sizep)
 		case CKA_PRIVATE:
 			size = sizeof(CK_BBOOL); break;
 		case CKA_CERTIFICATE_TYPE:
-			size = sizeof(CK_ULONG); break;
+			size = sizeof(CK_CERTIFICATE_TYPE); break;
 		case CKA_MODULUS_BITS:
 			size = sizeof(CK_ULONG); break;
 		case CKA_OBJECT_ID: