diff --git a/library/ssl_tls12_server.c b/library/ssl_tls12_server.c
index c791f81..26d570a 100644
--- a/library/ssl_tls12_server.c
+++ b/library/ssl_tls12_server.c
@@ -2682,6 +2682,7 @@
                 break;
             }
 
+            mbedtls_platform_zeroize(buf, sizeof(buf));
             ret = 0;
             break;
 #endif /* !MBEDTLS_PK_USE_PSA_EC_DATA */