diff --git a/tests/suites/test_suite_pk.function b/tests/suites/test_suite_pk.function
index 4813f71..c7c7075 100644
--- a/tests/suites/test_suite_pk.function
+++ b/tests/suites/test_suite_pk.function
@@ -246,7 +246,8 @@
     TEST_ASSERT( mbedtls_ecp_point_read_binary( &eckey->grp, &eckey->Q,
                                         key->x, key->len ) == 0 );
 
-    TEST_ASSERT( mbedtls_pk_verify( &pk, MBEDTLS_MD_NONE,
+    // MBEDTLS_MD_SHA1 is a dummy - it is ignored, but has to be other than MBEDTLS_MD_NONE.
+    TEST_ASSERT( mbedtls_pk_verify( &pk, MBEDTLS_MD_SHA1,
                             hash->x, hash->len, sig->x, sig->len ) == ret );
 
 exit: