CVE-2026-56149Network attack vector

Admin-triggered node outage via machine-learning memory exhaustion

Published Jul 1, 2026 · Updated Jul 1, 2026

Resource exhaustion in Elastic Elasticsearch allows remote authenticated users with elevated privileges to make an affected node unavailable. A specially crafted machine-learning request causes excessive memory consumption, although Elastic has not disclosed the request field or allocation path that lacks a limit. Only deployments using machine learning are exposed, and exploitation requires privileges to create or manage trained models; affected releases are 8.0.0 through 8.19.16, 9.0.0 through 9.3.5, and 9.4.0 through 9.4.2.

CVSS severity4.9
Medium
EPSS probability0.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in Elastic Elasticsearch allows remote authenticated users with elevated privileges to make an affected node unavailable. A specially crafted machine-learning request causes excessive memory consumption, although Elastic has not disclosed the request field or allocation path that lacks a limit. Only deployments using machine learning are exposed, and exploitation requires privileges to create or manage trained models; affected releases are 8.0.0 through 8.19.16, 9.0.0 through 9.3.5, and 9.4.0 through 9.4.2.

The record

CVE
CVE-2026-56149
Published
Jul 1, 2026
Updated
Jul 1, 2026
Vendor
Elastic
Product
Elasticsearch
Classifications
CWE-770, CAPEC-130, T1499.004
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jul 1, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=8.0.0 <=8.19.16
  2. Affected versionversion=9.0.0 <=9.3.5
  3. Affected versionversion=9.4.0 <=9.4.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Elastic · Elasticsearchversion=8.0.0 <=8.19.16; version=9.0.0 <=9.3.5; version=9.4.0 <=9.4.2

Published CVSS scores

4.9ElasticCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
CAPEC-130Excessive Allocation
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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