diff --git a/http_parser.c b/http_parser.c
index ba1374e9..0b9c83e0 100644
--- a/http_parser.c
+++ b/http_parser.c
@@ -1424,12 +1424,6 @@ size_t http_parser_execute (http_parser *parser,
               goto error;
             }
 
-            if (parser->flags & F_CONTENTLENGTH) {
-              SET_ERRNO(HPE_UNEXPECTED_CONTENT_LENGTH);
-              goto error;
-            }
-
-            parser->flags |= F_CONTENTLENGTH;
             parser->content_length = ch - '0';
             parser->header_state = h_content_length_num;
             break;
@@ -1695,6 +1689,21 @@ size_t http_parser_execute (http_parser *parser,
           case h_connection_upgrade:
             parser->flags |= F_CONNECTION_UPGRADE;
             break;
+          case h_content_length_num:
+          case h_content_length_ws:
+            if (parser->flags & F_CONTENTLENGTH) {
+                /* content length sent multiple times,
+                 * check if value is the same */
+                if (parser->initial_content_length != parser->content_length) {
+                    SET_ERRNO(HPE_UNEXPECTED_CONTENT_LENGTH);
+                    goto error;
+                }
+            } else {
+                /* set content length flag */
+                parser->flags |= F_CONTENTLENGTH;
+                parser->initial_content_length = parser->content_length;
+            }
+            break;
           default:
             break;
         }
diff --git a/http_parser.h b/http_parser.h
index e894d7ce..684befad 100644
--- a/http_parser.h
+++ b/http_parser.h
@@ -301,6 +301,7 @@ struct http_parser {
 
   uint32_t nread;          /* # bytes read in various scenarios */
   uint64_t content_length; /* # bytes in body (0 if no Content-Length header) */
+  uint64_t initial_content_length; /* # used to verify same value if Content-Length header occurs multiple times */
 
   /** READ-ONLY **/
   unsigned short http_major;