Incorrect Authorization in Kibana Leading to Unauthorized Deletion of Synthetics Private Locations
Description:
Incorrect Authorization (CWE-863) in Kibana can lead to unauthorized deletion of Synthetics private locations via Accessing Functionality Not Properly Constrained by ACLs (CAPEC-1). Synthetics private locations can be shared with more than one space, and deleting one removes it from every space it is shared with. The safeguard that prevented the deletion of a private location still in use evaluated only the monitors visible in the requesting user's own space, so monitors that depend on the private location in other spaces were not taken into account.
As a result, an authenticated Kibana user holding the Synthetics write privilege in a single space could delete a private location that other spaces still depend on, even where the user has no access to those spaces. Deleting the private location removes the shared configuration and stops the monitors in the other spaces from running, which suppresses the availability monitoring those spaces rely on.
Affected Versions:
- 8.x: All versions up to and including 8.19.19
- 9.x: All versions from 9.0.0 up to and including 9.4.3
Affected Configurations:
Kibana deployments that use Synthetics with private locations shared across more than one space, and in which at least one user holds the Synthetics write privilege in only a subset of those spaces. Single-space deployments are not affected, because there is no cross-space boundary to bypass. Both self-managed and Elastic Cloud Hosted deployments are affected. No non-default configuration is required.
Solutions and Mitigations:
The issue is resolved in versions 8.19.20, and 9.4.4.
For Users that Cannot Upgrade:
- Do not share a Synthetics private location across multiple spaces. A private location confined to a single space cannot be deleted by a user outside that space.
- Grant the Synthetics write privilege only to users who are trusted with every space that a shared private location is used in. Removing this privilege also removes the ability to create and edit private locations and monitors in that space.
Indicators of Compromise (IOC)
Review Kibana audit logs for deletions of Synthetics private locations carried out by accounts that do not administer all of the spaces the location was shared with. A private location that disappears while monitors in another space stop producing results, with no corresponding change request from the owners of that space, is consistent with exploitation.
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 ( 5.4 ) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
CVE ID: CVE-2026-72673
Problem Type: CWE-863 - Incorrect Authorization
Impact: CAPEC-1 - Accessing Functionality Not Properly Constrained by ACLs