Security

• Disable dynamic Groovy scripting by marking Groovy as not sandboxed. #9655

Enhancements

• Core:
  • Fix Store.checkIntegrity() for lucene 3.x index files. #9234
  • Don't verify adler32 for lucene 3.x terms dict/terms index. #9142
• Mapping:
  • Include currentFieldName into ObjectMapper errors #9020
• Recovery:
  • add a timeout to local mapping change check #9575
• Scripting:
  • Make script.groovy.sandbox.method_blacklist_patch truly append-only #9473
  • Make groovy sandbox method blacklist dynamically additive #9470

Bug fixes

• Aggs:
  • In reverse nested aggregation, fix handling of the same child doc id being processed multiple times. #9345 (issues: #9263, #9346)
  • The parent filter of the nested aggregator isn't resolved correctly all the time #9335 (issue: #9280)
• Allocation:
  • Weight deltas must be absolute deltas #9149 (issue: #9023)
• Core:
  • Mapping update task back references already closed index shard #9607
  • Terms filter lookup caching should cache values, not filters. #9027 (issues: #1, #2)
• Internal:
  • promptly cleanup updateTask timeout handler #9621
• Mapping:
  • Throw StrictDynamicMappingException exception #9445 (issue: #9444)
• Percolator:
  • Fixed bug when using multi percolate api with routing #9161 (issue: #6214)
• REST:
  • Add fielddata_fields to the REST spec #9399 (issues: #4492, #9398)
• Scripting:
  • Disallow method pointer expressions in Groovy scripting #9509
• Search:
  • Make sure that named filters/ queries defined in a wrapped query/filters aren't lost #9166 (issue: #6871)
• Settings:
  • cluster.routing.allocation.disk.threshold_enabled accepts wrong values #9309
• Stats:
  • Relax restrictions on filesystem size reporting in DiskUsage #9283 (issues: #9249, #9260)
• Tribe node:
  • remove closed indices from cluster state #9334