diff --git a/library/ssl_ticket.c b/library/ssl_ticket.c
index 7f65849..a9036a2 100644
--- a/library/ssl_ticket.c
+++ b/library/ssl_ticket.c
@@ -70,7 +70,7 @@
                                unsigned char index )
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-    unsigned char buf[MAX_KEY_BYTES];
+    unsigned char buf[MAX_KEY_BYTES] = {0};
     mbedtls_ssl_ticket_key *key = ctx->keys + index;
 
 #if defined(MBEDTLS_USE_PSA_CRYPTO)