SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-72687

A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single small request containing a forged opaque identifier.

MEDIUM 6.5EPSS 0.30%

Does this matter?

Lower severity and a low EPSS score (0.30%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 3.1
6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.30% probability · 22th percentile
CISA KEV
Not listed
Weakness
CWE-789
Affected
elastic/elasticsearch
Source
security@elastic.co

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.