CVE-2026-72687 PUBLISHED

Memory Allocation with Excessive Size Value in Elasticsearch Leading to Denial of Service

Assigner: elastic
Reserved: 10.08.2026 Published: 13.08.2026 Updated: 13.08.2026

A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single small request containing a forged opaque identifier. Elasticsearch decodes and deserializes the identifier before confirming that it was legitimately issued by the cluster, and a size value carried inside the identifier drives an allocation that is neither capped nor accounted for by the available memory-usage controls. The resulting out-of-memory condition is fatal and terminates the affected node process, resulting in a denial of service.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 6.5

Product Status

Vendor Elastic
Product Elasticsearch
Versions Default: unaffected
  • affected from 8.0.0 to 8.19.19 (incl.)
  • affected from 9.0.0 to 9.4.4 (incl.)
  • Version 9.5.0 is affected

References

Problem Types

  • CWE-789 Memory Allocation with Excessive Size Value CWE