diff --git a/tests/psa-client-server/psasim/src/psa_sim_crypto_client.c b/tests/psa-client-server/psasim/src/psa_sim_crypto_client.c
index 635a70545a..9051f20535 100644
--- a/tests/psa-client-server/psasim/src/psa_sim_crypto_client.c
+++ b/tests/psa-client-server/psasim/src/psa_sim_crypto_client.c
@@ -73,12 +73,12 @@ int psa_crypto_call(int function,
 
 psa_status_t psa_crypto_init(void)
 {
-    char mbedtls_version[18];
+    const char *mbedtls_version;
     uint8_t *result = NULL;
     size_t result_length;
     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
 
-    mbedtls_version_get_string_full(mbedtls_version);
+    mbedtls_version = mbedtls_version_get_string_full();
     CLIENT_PRINT("%s", mbedtls_version);
 
     CLIENT_PRINT("My PID: %d", getpid());
diff --git a/tests/psa-client-server/psasim/src/psa_sim_generate.pl b/tests/psa-client-server/psasim/src/psa_sim_generate.pl
index 3eec226e16..0f4c86f817 100755
--- a/tests/psa-client-server/psasim/src/psa_sim_generate.pl
+++ b/tests/psa-client-server/psasim/src/psa_sim_generate.pl
@@ -390,12 +390,12 @@ int psa_crypto_call(int function,
 
 psa_status_t psa_crypto_init(void)
 {
-    char mbedtls_version[18];
+    const char *mbedtls_version;
     uint8_t *result = NULL;
     size_t result_length;
     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
 
-    mbedtls_version_get_string_full(mbedtls_version);
+    mbedtls_version = mbedtls_version_get_string_full();
     CLIENT_PRINT("%s", mbedtls_version);
 
     CLIENT_PRINT("My PID: %d", getpid());
diff --git a/tests/psa-client-server/psasim/src/server.c b/tests/psa-client-server/psasim/src/server.c
index 44939f1c2a..aa0c75a488 100644
--- a/tests/psa-client-server/psasim/src/server.c
+++ b/tests/psa-client-server/psasim/src/server.c
@@ -56,8 +56,7 @@ int psa_server_main(int argc, char *argv[])
     extern psa_status_t psa_crypto_close(void);
 
 #if defined(MBEDTLS_VERSION_C)
-    char mbedtls_version[18];
-    mbedtls_version_get_string_full(mbedtls_version);
+    const char *mbedtls_version = mbedtls_version_get_string_full();
     SERVER_PRINT("%s", mbedtls_version);
 #endif