CVE-2026-26936Network attack vector

Service interruption via exponential regex backtracking

Published Feb 26, 2026 · Updated Feb 26, 2026

Inefficient regex handling in Kibana 8.0.0 through 8.19.10 and 9.0.0 through 9.2.4 allows remote authenticated users to interrupt service. The AI Inference Anonymization Engine processes custom anonymization regular expressions with exponential worst-case backtracking, exhausting processing resources. Exploitation requires high privileges, an explicitly configured AI connector, the enabled AI Assistant, and custom anonymization rules; the affected pipeline can make Kibana unresponsive.

CVSS severity4.9
Medium
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Inefficient regex handling in Kibana 8.0.0 through 8.19.10 and 9.0.0 through 9.2.4 allows remote authenticated users to interrupt service. The AI Inference Anonymization Engine processes custom anonymization regular expressions with exponential worst-case backtracking, exhausting processing resources. Exploitation requires high privileges, an explicitly configured AI connector, the enabled AI Assistant, and custom anonymization rules; the affected pipeline can make Kibana unresponsive.

The record

CVE
CVE-2026-26936
Published
Feb 26, 2026
Updated
Feb 26, 2026
Vendor
Elastic
Product
Kibana
Classifications
CWE-1333, CAPEC-492, T1499.004
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Feb 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 26, 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 <=8.19.10
  2. Affected versionversion=9.0.0 <=9.2.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Elastic · Kibanaversion=8.0.0 <=8.19.10; version=9.0.0 <=9.2.4

Published CVSS scores

7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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-1333Inefficient Regular Expression Complexity
CAPEC-492Regular Expression Exponential Blowup
T1499.004Endpoint Denial of Service: Application 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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