diff --git a/mfapi/mfconn.c b/mfapi/mfconn.c
index 93fca58..09b2756 100644
--- a/mfapi/mfconn.c
+++ b/mfapi/mfconn.c
@@ -156,6 +156,10 @@ const char     *mfconn_create_call_signature(mfconn * conn, const char *url,
     signature_raw = strdup_printf("%d%s%s%s",
                                   (conn->secret_key % 256),
                                   conn->secret_time, api, args);
+    if (signature_raw == NULL) {
+        fprintf(stderr, "strdup_printf failed\n");
+        return NULL;
+    }
 
     MD5((const unsigned char *)signature_raw,
         strlen(signature_raw), signature_enc);
@@ -239,6 +243,11 @@ const char     *mfconn_create_signed_get(mfconn * conn, int ssl,
 
     // append api GET args to api request
     api_request = (char *)realloc(api_request, bytes_to_alloc);
+    if (api_request == NULL) {
+        fprintf(stderr, "cannot allocate memory\n");
+        return NULL;
+    }
+
     strncat(api_request, api_args, api_args_len);
     strcat(api_request, signature);
 
diff --git a/utils/strings.c b/utils/strings.c
index 4849678..e17f7e0 100644
--- a/utils/strings.c
+++ b/utils/strings.c
@@ -42,6 +42,10 @@ char           *strdup_printf(char *fmt, ...)
     bytes_to_allocate++;
 
     ret_str = (char *)malloc(bytes_to_allocate * sizeof(char));
+    if (ret_str == NULL) {
+        fprintf(stderr, "failed to allocate memory\n");
+        return NULL;
+    }
 
     va_start(ap, fmt);
     bytes_to_allocate = vsnprintf(ret_str, bytes_to_allocate, fmt, ap);
diff --git a/valgrind.supp b/valgrind.supp
index c63204e..d2fccd6 100644
--- a/valgrind.supp
+++ b/valgrind.supp
@@ -58,11 +58,58 @@
    ...
    fun:curl_multi_perform
    fun:curl_easy_perform
-   fun:http_post_buf
-   fun:mfconn_api_user_get_session_token
-   fun:mfconn_create
-   fun:mfshell_cmd_auth
-   fun:mfshell_exec
-   fun:mfshell_parse_commands
-   fun:main
+   ...
+}
+{
+   libcurl #1
+   Memcheck:Leak
+   ...
+   fun:curl_global_init
+   fun:curl_easy_init
+   ...
+}
+{
+   libcurl #2
+   Memcheck:Cond
+   ...
+   fun:curl_multi_perform
+   fun:curl_easy_perform
+   ...
+}
+{
+   libcurl #3
+   Memcheck:Value8
+   fun:Curl_raw_toupper
+   ...
+}
+{
+   libcrypto
+   Memcheck:Leak
+   ...
+   fun:curl_multi_perform
+   fun:curl_easy_perform
+   ...
+}
+{
+   openssl
+   Memcheck:Leak
+   fun:malloc
+   fun:CRYPTO_malloc
+   ...
+   fun:ssl_verify_cert_chain
+   ...
+}
+{
+   jansson #1
+   Memcheck:Cond
+   ...
+   obj:*/libjansson.so*
+   ...
+}
+{
+   jansson #2
+   Memcheck:Value8
+   ...
+   obj:*/libjansson.so*
+   ...
 }