CVE-2026-42397Network attack vector

Authenticated denial of service via oversized input

Published Jul 21, 2026 · Updated Jul 21, 2026

Resource exhaustion in Elastic Kibana 9.3.0 through 9.3.6 and 9.4.0 through 9.4.3 allows remote authenticated users to interrupt service. Affected Entity Analytics endpoints accept an oversized input value without resource limits, causing excessive allocation and resource consumption. Any authenticated account that can submit the crafted request can make the Kibana instance unavailable, with no reported data disclosure or modification.

CVSS severity6.5
Medium
EPSS probability0.42%
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 Kibana 9.3.0 through 9.3.6 and 9.4.0 through 9.4.3 allows remote authenticated users to interrupt service. Affected Entity Analytics endpoints accept an oversized input value without resource limits, causing excessive allocation and resource consumption. Any authenticated account that can submit the crafted request can make the Kibana instance unavailable, with no reported data disclosure or modification.

The record

CVE
CVE-2026-42397
Published
Jul 21, 2026
Updated
Jul 21, 2026
Vendor
Elastic
Product
Kibana
Classifications
CWE-770, CAPEC-130, T1499
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=9.3.0 <=9.3.6
  2. Affected versionversion=9.4.0 <=9.4.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Elastic · Kibanaversion=9.3.0 <=9.3.6; 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 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-770Allocation of Resources Without Limits or Throttling
CAPEC-130Excessive Allocation
T1499Endpoint Denial of Service

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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