diff --git a/src/test_helpers/ssl_helpers.c b/src/test_helpers/ssl_helpers.c
index 89c1bbf52..9c1676fc6 100644
--- a/src/test_helpers/ssl_helpers.c
+++ b/src/test_helpers/ssl_helpers.c
@@ -1794,11 +1794,11 @@ int mbedtls_test_ssl_tls13_populate_session(mbedtls_ssl_session *session,
 #if defined(MBEDTLS_SSL_EARLY_DATA)
     session->max_early_data_size = 0x87654321;
 #if defined(MBEDTLS_SSL_ALPN) && defined(MBEDTLS_SSL_SRV_C)
-    session->alpn = mbedtls_calloc(strlen("ALPNExample")+1, sizeof(char));
-    if (session->alpn == NULL) {
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    ret = mbedtls_ssl_session_set_alpn(session, "ALPNExample");
+    if (ret != 0) {
         return -1;
     }
-    strcpy(session->alpn, "ALPNExample");
 #endif /* MBEDTLS_SSL_ALPN && MBEDTLS_SSL_SRV_C */
 #endif /* MBEDTLS_SSL_EARLY_DATA */