# Kibana 8.19.21, 9.4.6, 9.5.3 Security Update (ESA-2026-154)

**URL:** <https://discuss.elastic.co/t/kibana-8-19-21-9-4-6-9-5-3-security-update-esa-2026-154/390161>\
**Category:** Security Announcements\
**Created:** [September 3, 2026, 6:02pm UTC](https://discuss.elastic.co/t/kibana-8-19-21-9-4-6-9-5-3-security-update-esa-2026-154/390161 "2026-09-03T18:02:15Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Bryan\_Garcia](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/bryan_garcia/32/148179_2.png) [@Bryan\_Garcia](https://discuss.elastic.co/u/Bryan_Garcia)\
**Post date:** [September 3, 2026, 6:02pm UTC](https://discuss.elastic.co/t/kibana-8-19-21-9-4-6-9-5-3-security-update-esa-2026-154/390161/1 "2026-09-03T18:02:15Z")

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**Missing Authorization in Kibana Leading to Unauthorized Cross-Space Write Operations**

Missing Authorization in Kibana Leading to Unauthorized Modification of Data / Missing Authorization (CWE-862) in Kibana can lead to unauthorized modification of data via Privilege Abuse (CAPEC-122). An authenticated user holding Security read-level access in a single Kibana space could trigger Entity Analytics migration operations that perform privileged writes across all Kibana spaces, regardless of that user's actual access scope.

**Affected Versions:**

- 8.x: All versions from 8.18.3 up to and including 8.19.20
- 9.x:
  - All versions from 9.0.3 up to and including 9.4.5
  - All versions from 9.5.0 up to and including 9.5.2

**Affected Configurations:**  
All Kibana deployments where the Entity Analytics feature has been initialized in at least one space are affected. Multi-space deployments face a broader impact due to the cross-space nature of the unauthorized operation; however, the underlying authorization deficiency is present regardless of space count.

**Solutions and Mitigations:**  
The issue is resolved in Kibana versions 8.19.21, 9.4.6, and 9.5.3.

**For Users that Cannot Upgrade:**  
There are no workarounds for this vulnerability.

**Indicators of Compromise (IOC)**  
No specific indicators of compromise have been identified for this vulnerability.

**Elastic Cloud Serverless**

Due to our continuous deployment and patching model, the vulnerability described in this security advisory was remediated in our Elastic Cloud Serverless offering before the public disclosure.

**Severity:** CVSSv3.1: Medium ( 4.3 ) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N  
**CVE ID:** CVE-2026-78596  
**Problem Type:** CWE-862 - Missing Authorization  
**Impact:** CAPEC-122 - Privilege Abuse