Malformed content; must start with an object – Elasticsearch Error How To Solve Related Issues

Malformed content; must start with an object – Elasticsearch Error How To Solve Related Issues

Updated: July-20

Elasticsearch Version: 1.7-8.0

Before you begin reading this guide, we recommend you try running the Elasticsearch Error Check-Up  which can resolve issues causing many errors 


This guide will help you check for common problems that cause the log “Malformed content; must start with an object” to appear. It’s important to understand the issues related to the log, so to get started, read the general overview on common issues and tips related to the Elasticsearch concepts: index.

Advanced users might want to skip right to the common problems section in each concept or try running the Check-Up which analyses ES to discover the cause of many errors and provides suitable actionable recommendations (free tool that requires no installation). 

Log Context

Log”Malformed content; must start with an object”classname  is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

private static void validateStart(XContentParser parser) throws IOException {
  // will result in START_OBJECT
  XContentParser.Token token = parser.nextToken();
  if (token != XContentParser.Token.START_OBJECT) {
  throw new MapperParsingException("Malformed content; must start with an object");
  private static void validateEnd(XContentParser parser) throws IOException {
  XContentParser.Token token;// only check for end of tokens if we created the parser here


Related issues to this log

We have gathered selected Q&A from the community and issues from Github, that can help fix related issues please review the following for further information :

1 {"error":"MapperParsingException[Malformed content, must start with an object]","status":400} -views 2,520 ,score 3

Elastic search – manual json indexing -views   711



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