### Elasticsearch Version

8.6.0

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

docker-image = docker.elastic.co/elasticsearch/elasticsearch:8.6

### Problem Description

We are trying to migrate from Elasticsearch 6.7.1 to Elasticsearch 8.6.0.

With the same document we always get IndexOutOfBoundsException while trying to fetch innerhits in Elasticsearch 8.6.0. Everything works fine in Elasticsearch 6.7.1.


### Steps to Reproduce

[elasticsearch_6.7.1 (1).txt](https://github.com/elastic/elasticsearch/files/10466823/elasticsearch_6.7.1.1.txt)
[elasticsearch_8.6.0.txt](https://github.com/elastic/elasticsearch/files/10466824/elasticsearch_8.6.0.txt)


### Logs (if relevant)

`{"@timestamp":"2023-01-20T13:39:21.170Z", "log.level": "WARN", "message":"path: /test/_search, params: {index=test}", "ecs.version": "1.2.0","service.name":"ES_ECS","event.dataset":"elasticsearch.server","process.thread.name":"elasticsearch[es01][search][T#10]","log.logger":"rest.suppressed","elasticsearch.cluster.uuid":"T3_Kb_fZTOORKN7Bn5jz2g","elasticsearch.node.id":"fESFHfZ-RxuDaPIIKhOoNA","elasticsearch.node.name":"es01","elasticsearch.cluster.name":"es_alex","error.type":"org.elasticsearch.action.search.SearchPhaseExecutionException","error.message":"all shards failed","error.stack_trace":"Failed to execute phase [query], all shards failed; shardFailures {[fESFHfZ-RxuDaPIIKhOoNA][test][0]: org.elasticsearch.transport.RemoteTransportException: [es01][172.27.0.2:9300][indices:data/read/search[phase/query]]\nCaused by: org.elasticsearch.search.fetch.FetchPhaseExecutionException: Fetch Failed [Error running fetch phase for doc [73]]\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.buildSearchHits(FetchPhase.java:181)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.execute(FetchPhase.java:93)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.SearchService.executeFetchPhase(SearchService.java:659)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.SearchService.executeQueryPhase(SearchService.java:634)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.SearchService.lambda$executeQueryPhase$2(SearchService.java:489)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.ActionRunnable.lambda$supply$0(ActionRunnable.java:47)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.ActionRunnable$2.doRun(ActionRunnable.java:62)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:26)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.common.util.concurrent.TimedRunnable.doRun(TimedRunnable.java:33)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:769)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:26)\n\tat java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)\n\tat java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)\n\tat java.base/java.lang.Thread.run(Thread.java:833)\nCaused by: org.elasticsearch.search.fetch.FetchPhaseExecutionException: Fetch Failed [Error running fetch phase for doc [43]]\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.buildSearchHits(FetchPhase.java:181)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.execute(FetchPhase.java:93)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.subphase.InnerHitsPhase.hitExecute(InnerHitsPhase.java:76)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.subphase.InnerHitsPhase$1.process(InnerHitsPhase.java:52)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.buildSearchHits(FetchPhase.java:177)\n\t... 13 more\nCaused by: java.lang.IndexOutOfBoundsException: Index: 43, Size: 1\n\tat java.base/java.util.Collections$SingletonList.get(Collections.java:4959)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.prepareNestedHitContext(FetchPhase.java:466)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.prepareHitContext(FetchPhase.java:312)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.buildSearchHits(FetchPhase.java:165)\n\t... 17 more\n}\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.search.AbstractSearchAsyncAction.onPhaseFailure(AbstractSearchAsyncAction.java:728)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.search.AbstractSearchAsyncAction.executeNextPhase(AbstractSearchAsyncAction.java:418)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.search.AbstractSearchAsyncAction.onPhaseDone(AbstractSearchAsyncAction.java:760)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.search.AbstractSearchAsyncAction.onShardFailure(AbstractSearchAsyncAction.java:512)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.search.AbstractSearchAsyncAction$1.onFailure(AbstractSearchAsyncAction.java:349)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.ActionListener$Delegating.onFailure(ActionListener.java:92)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.ActionListenerResponseHandler.handleException(ActionListenerResponseHandler.java:48)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.search.SearchTransportService$ConnectionCountingHandler.handleException(SearchTransportService.java:642)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.transport.TransportService$UnregisterChildTransportResponseHandler.handleException(TransportService.java:1650)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.transport.TransportService$ContextRestoreResponseHandler.handleException(TransportService.java:1390)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.transport.TransportService$DirectResponseChannel.processException(TransportService.java:1512)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.transport.TransportService$DirectResponseChannel.sendResponse(TransportService.java:1487)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.transport.TaskTransportChannel.sendResponse(TaskTransportChannel.java:50)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.support.ChannelActionListener.onFailure(ChannelActionListener.java:48)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.ActionRunnable.onFailure(ActionRunnable.java:77)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:28)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.common.util.concurrent.TimedRunnable.doRun(TimedRunnable.java:33)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:769)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:26)\n\tat java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)\n\tat java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)\n\tat java.base/java.lang.Thread.run(Thread.java:833)\nCaused by: org.elasticsearch.ElasticsearchException$1: Index: 43, Size: 1\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.ElasticsearchException.guessRootCauses(ElasticsearchException.java:638)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.search.AbstractSearchAsyncAction.executeNextPhase(AbstractSearchAsyncAction.java:416)\n\t... 20 more\nCaused by: java.lang.IndexOutOfBoundsException: Index: 43, Size: 1\n\tat java.base/java.util.Collections$SingletonList.get(Collections.java:4959)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.prepareNestedHitContext(FetchPhase.java:466)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.prepareHitContext(FetchPhase.java:312)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.buildSearchHits(FetchPhase.java:165)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.execute(FetchPhase.java:93)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.subphase.InnerHitsPhase.hitExecute(InnerHitsPhase.java:76)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.subphase.InnerHitsPhase$1.process(InnerHitsPhase.java:52)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.buildSearchHits(FetchPhase.java:177)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.fetch.FetchPhase.execute(FetchPhase.java:93)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.SearchService.executeFetchPhase(SearchService.java:659)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.SearchService.executeQueryPhase(SearchService.java:634)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.search.SearchService.lambda$executeQueryPhase$2(SearchService.java:489)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.ActionRunnable.lambda$supply$0(ActionRunnable.java:47)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.action.ActionRunnable$2.doRun(ActionRunnable.java:62)\n\tat org.elasticsearch.server@8.4.3/org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:26)\n\t... 6 more\n"}`
server/src/main/java/org/elasticsearch/index/mapper/DocumentParser.java
}
                    parseCopyFields(context, copyToFields);
                }
            }
        } else if (mapper instanceof FieldAliasMapper) {
            throwOnCopyToOnFieldAlias(context, mapper);
        } else {
            throwOnUnrecognizedMapperType(mapper);
        }
    }
    private static void throwOnUnrecognizedMapperType(Mapper mapper) {
        throw new IllegalStateException(
            "The provided mapper [" + mapper.name() + "] has an unrecognized type [" + mapper.getClass().getSimpleName() + "]."
        );
    }
    private static void throwOnCopyToOnFieldAlias(DocumentParserContext context, Mapper mapper) {
        throw new MapperParsingException(
            "Cannot " + (context.isWithinCopyTo() ? "copy" : "write") + " to a field alias [" + mapper.name() + "]."
        );
    }
    private static void throwOnCopyToOnObject(Mapper mapper, List<String> copyToFields) {
        throw new MapperParsingException(
            "Cannot copy field ["
                + mapper.name()
                + "] to fields "
                + copyToFields
                + ". Copy-to currently only works for value-type fields, not objects."
        );
    }
    private static void parseObject(final DocumentParserContext context, ObjectMapper parentObjectMapper, String currentFieldName)