CVE-2026-72639Network attack vector

Authenticated node crash via unbounded highlighting allocation

Published Aug 13, 2026 · Updated Aug 13, 2026

Denial of service in Elastic Elasticsearch 8.19.0 through 8.19.19 and 9.3.0 through 9.5.0 allows remote authenticated users to crash a node. A search highlighting option accepts an unbounded user-supplied count and allocates an excessively large structure outside circuit-breaker accounting before highlighting limits run. Read privileges on one index containing a text field are sufficient; one small REST request can exhaust memory, terminate the node process, and degrade cluster health.

CVSS severity6.5
Medium
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Elastic Elasticsearch 8.19.0 through 8.19.19 and 9.3.0 through 9.5.0 allows remote authenticated users to crash a node. A search highlighting option accepts an unbounded user-supplied count and allocates an excessively large structure outside circuit-breaker accounting before highlighting limits run. Read privileges on one index containing a text field are sufficient; one small REST request can exhaust memory, terminate the node process, and degrade cluster health.

The record

CVE
CVE-2026-72639
Published
Aug 13, 2026
Updated
Aug 13, 2026
Vendor
Elastic
Product
Elasticsearch
Classifications
CWE-789, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 13, 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=8.19.0 <=8.19.19
  2. Affected versionversion=9.3.0 <=9.5.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Elastic · Elasticsearchversion=8.19.0 <=8.19.19; version=9.3.0 <=9.5.0

Published CVSS scores

6.5ElasticCVSS:3.1/AV:N/AC:L/PR:L/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-789Memory Allocation with Excessive Size Value
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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