CVE-2026-63263Network attack vector

Authenticated service interruption via exponential ES|QL evaluation

Published Jul 21, 2026 · Updated Jul 21, 2026

Uncontrolled resource consumption in Elasticsearch allows remote authenticated users to interrupt ES|QL service with a crafted query. The ES|QL engine evaluates specially crafted queries with exponentially increasing CPU consumption, and exhausted query workers remain unavailable after evaluation ends. Affected 8.0.0 through 8.19.18, 9.0.0 through 9.3.7, and 9.4.0 through 9.4.3 deployments expose the condition to users allowed to run ES|QL queries; repeated requests block ES|QL until node restart.

CVSS severity6.5
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled resource consumption in Elasticsearch allows remote authenticated users to interrupt ES|QL service with a crafted query. The ES|QL engine evaluates specially crafted queries with exponentially increasing CPU consumption, and exhausted query workers remain unavailable after evaluation ends. Affected 8.0.0 through 8.19.18, 9.0.0 through 9.3.7, and 9.4.0 through 9.4.3 deployments expose the condition to users allowed to run ES|QL queries; repeated requests block ES|QL until node restart.

The record

CVE
CVE-2026-63263
Published
Jul 21, 2026
Updated
Jul 21, 2026
Vendor
Elastic
Product
Elasticsearch
Classifications
CWE-400, CAPEC-197, T1499.003
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 21, 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 <=8.19.18
  2. Affected versionversion=9.0.0 <=9.3.7
  3. Affected versionversion=9.4.0 <=9.4.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Elastic · Elasticsearchversion=8.0.0 <=8.19.18; version=9.0.0 <=9.3.7; version=9.4.0 <=9.4.3

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
CAPEC-197Exponential Data Expansion
T1499.003Application Exhaustion Flood

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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