diff --git a/mfapi/apicalls/upload_simple.c b/mfapi/apicalls/upload_simple.c
index 7da69cf..5070538 100644
--- a/mfapi/apicalls/upload_simple.c
+++ b/mfapi/apicalls/upload_simple.c
@@ -25,10 +25,13 @@
 #include <stddef.h>
 #include <stdio.h>
 #include <stdint.h>
+#include <inttypes.h>
 #include <openssl/sha.h>
+#include <curl/curl.h>
 
 #include "../../utils/http.h"
 #include "../../utils/hash.h"
+#include "../../utils/strings.h"
 #include "../mfconn.h"
 #include "../apicalls.h"        // IWYU pragma: keep
 
@@ -45,6 +48,8 @@ mfconn_api_upload_simple(mfconn * conn, const char *folderkey,
     char           *file_hash;
     uint64_t        file_size;
     int             i;
+    struct curl_slist *custom_headers = NULL;
+    char           *tmpheader;
 
     if (conn == NULL)
         return -1;
@@ -70,6 +75,10 @@ mfconn_api_upload_simple(mfconn * conn, const char *folderkey,
             free(*upload_key);
             *upload_key = NULL;
         }
+        if (custom_headers != NULL) {
+            curl_slist_free_all(custom_headers);
+            custom_headers = NULL;
+        }
 
         if (folderkey == NULL) {
             api_call = mfconn_create_signed_get(conn, 0,
@@ -85,13 +94,28 @@ mfconn_api_upload_simple(mfconn * conn, const char *folderkey,
         // make sure that we are at the beginning of the file
         rewind(fh);
 
+        // the following three pseudo headers are interpreted by the mediafire
+        // server
+        tmpheader = strdup_printf("x-filename: %s", file_name);
+        custom_headers = curl_slist_append(custom_headers, tmpheader);
+        free(tmpheader);
+        tmpheader = strdup_printf("x-filesize: %" PRIu64, file_size);
+        custom_headers = curl_slist_append(custom_headers, tmpheader);
+        free(tmpheader);
+        tmpheader = strdup_printf("x-filehash: %s", file_hash);
+        custom_headers = curl_slist_append(custom_headers, tmpheader);
+        free(tmpheader);
+
         http = http_create();
-        retval = http_post_file(http, api_call, fh, file_name,
-                                file_size, file_hash,
+        retval = http_post_file(http, api_call, fh, &custom_headers, file_size,
                                 _decode_upload_simple, upload_key);
         http_destroy(http);
         mfconn_update_secret_key(conn);
 
+        if (custom_headers != NULL) {
+            curl_slist_free_all(custom_headers);
+            custom_headers = NULL;
+        }
         free((void *)api_call);
 
         if (retval != 127 && retval != 28)
diff --git a/utils/http.c b/utils/http.c
index 45e12b9..77ea749 100644
--- a/utils/http.c
+++ b/utils/http.c
@@ -21,11 +21,9 @@
 #include <curl/curl.h>
 #include <curl/easy.h>
 #include <stdbool.h>
-#include <inttypes.h>
 #include <stdio.h>
 
 #include "http.h"
-#include "strings.h"
 
 static int      http_progress_cb(void *user_ptr, double dltotal, double dlnow,
                                  double ultotal, double ulnow);
@@ -280,37 +278,25 @@ http_read_file_cb(char *data, size_t size, size_t nmemb, void *user_ptr)
 
 int
 http_post_file(mfhttp * conn, const char *url, FILE * fh,
-               const char *filename, uint64_t filesize, const char *fhash,
+               struct curl_slist **custom_headers, uint64_t filesize,
                int (*data_handler) (mfhttp * conn, void *data), void *data)
 {
-    struct curl_slist *custom_headers = NULL;
-    char           *tmpheader;
     int             retval;
 
     http_curl_reset(conn);
     conn->write_buf_len = 0;
 
-    // the following three pseudo headers are interpreted by the mediafire
-    // server
-    tmpheader = strdup_printf("x-filename: %s", filename);
-    custom_headers = curl_slist_append(custom_headers, tmpheader);
-    free(tmpheader);
-    tmpheader = strdup_printf("x-filesize: %" PRIu64, filesize);
-    custom_headers = curl_slist_append(custom_headers, tmpheader);
-    free(tmpheader);
-    tmpheader = strdup_printf("x-filehash: %s", fhash);
-    custom_headers = curl_slist_append(custom_headers, tmpheader);
-    free(tmpheader);
     // when using POST, curl implicitly sets
     // Content-Type: application/x-www-form-urlencoded
     // make sure it is set to application/octet-stream instead
-    custom_headers = curl_slist_append(custom_headers,
-                                       "Content-Type: application/octet-stream");
+    *custom_headers =
+        curl_slist_append(*custom_headers,
+                          "Content-Type: application/octet-stream");
     // when using POST, curl implicitly sets Expect: 100-continue
     // make sure it is not set
-    custom_headers = curl_slist_append(custom_headers, "Expect:");
+    *custom_headers = curl_slist_append(*custom_headers, "Expect:");
     curl_easy_setopt(conn->curl_handle, CURLOPT_POST, 1);
-    curl_easy_setopt(conn->curl_handle, CURLOPT_HTTPHEADER, custom_headers);
+    curl_easy_setopt(conn->curl_handle, CURLOPT_HTTPHEADER, *custom_headers);
     curl_easy_setopt(conn->curl_handle, CURLOPT_URL, url);
     curl_easy_setopt(conn->curl_handle, CURLOPT_READFUNCTION,
                      http_read_file_cb);
@@ -323,7 +309,8 @@ http_post_file(mfhttp * conn, const char *url, FILE * fh,
     conn->stream = fh;
     fprintf(stderr, "POST: %s\n", url);
     retval = curl_easy_perform(conn->curl_handle);
-    curl_slist_free_all(custom_headers);
+    curl_slist_free_all(*custom_headers);
+    *custom_headers = NULL;
     if (retval != CURLE_OK) {
         fprintf(stderr, "error curl_easy_perform %s\n\r", conn->error_buf);
         return retval;
diff --git a/utils/http.h b/utils/http.h
index 3981a73..a345098 100644
--- a/utils/http.h
+++ b/utils/http.h
@@ -22,6 +22,8 @@
 #include <jansson.h>
 #include <stddef.h>
 #include <stdint.h>
+#include <stdio.h>
+#include <curl/curl.h>
 
 typedef struct mfhttp mfhttp;
 
@@ -38,9 +40,9 @@ int             http_get_file(mfhttp * conn, const char *url,
                               const char *path);
 json_t         *http_parse_buf_json(mfhttp * conn, size_t flags,
                                     json_error_t * error);
-int             http_post_file(mfhttp * conn, const char *url,
-                               FILE * fh, const char *filename,
-                               uint64_t filesize, const char *fhash,
+int             http_post_file(mfhttp * conn, const char *url, FILE * fh,
+                               struct curl_slist **custom_headers,
+                               uint64_t filesize,
                                int (*data_handler) (mfhttp * conn, void *data),
                                void *data);