Description
A flaw in Elasticsearch allows an authenticated user with the privileges required to invoke the simulate pipeline API endpoint (https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-ingest-simulate) to submit a request that causes a self-referential data structure to be created. When a specific internal component later processes that structure, the operation recurses without bound and raises a fatal error that is not handled by the surrounding execution path, terminating the affected node process and resulting in a denial of service.
Affected products
elastic: elasticsearch
References1
- discuss.elastic.co/t/elasticsearch-8-19-19-9-3-8-9-4-4-security… Vendor Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 47 · as of 12 November 2026
- CWE
- CWE-674
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