diff --git a/library/ssl_tls13_generic.c b/library/ssl_tls13_generic.c
index 3ab6cc2..3d5baa2 100644
--- a/library/ssl_tls13_generic.c
+++ b/library/ssl_tls13_generic.c
@@ -864,6 +864,12 @@
     *algorithm = MBEDTLS_TLS1_3_SIG_NONE;
     for( ; *sig_alg != MBEDTLS_TLS1_3_SIG_NONE ; sig_alg++ )
     {
+        if( *sig_alg == MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA256 ||
+            *sig_alg == MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA384 ||
+            *sig_alg == MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA512 )
+        {
+            continue;
+        }
         if( mbedtls_ssl_sig_alg_is_supported( ssl, *sig_alg) &&
             mbedtls_ssl_tls13_sig_alg_is_available_for_pk(
                                               ssl, *sig_alg, own_key ) )