CVE-2026-76827Network attack vector

Cross-tenant data tampering via UID spoofing

Published Aug 19, 2026 · Updated Aug 19, 2026

Authorization flaw in Red Hat Advanced Cluster Management for Kubernetes lets remote authenticated users tamper with indexed search data. In search-indexer's delta-sync paths, UPDATE and DELETE mutations trust caller-supplied UIDs and never verify that the UID prefix or existing row owner matches the posting cluster; Bugzilla also notes an ON CONFLICT update path that can overwrite rows across cluster boundaries. Exploitation requires legitimate managed-cluster addon credentials and affects another cluster's search index, enabling cross-tenant overwrite or deletion of indexed resource data without control of the hub cluster itself.

CVSS severity6.8
Medium
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization flaw in Red Hat Advanced Cluster Management for Kubernetes lets remote authenticated users tamper with indexed search data. In search-indexer's delta-sync paths, UPDATE and DELETE mutations trust caller-supplied UIDs and never verify that the UID prefix or existing row owner matches the posting cluster; Bugzilla also notes an ON CONFLICT update path that can overwrite rows across cluster boundaries. Exploitation requires legitimate managed-cluster addon credentials and affects another cluster's search index, enabling cross-tenant overwrite or deletion of indexed resource data without control of the hub cluster itself.

The record

CVE
CVE-2026-76827
Published
Aug 19, 2026
Updated
Aug 19, 2026
Vendor
389 Directory Server
Product
Red Hat Advanced Cluster Management for Kubernetes
Classifications
CWE-693, T1565
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 19, 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?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

389 Directory Server · Red Hat Advanced Cluster Management for KubernetesAffected versions are unavailable in this record.

Published CVSS scores

6.8Red HatCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:N

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-693Protection Mechanism Failure
T1565Data Manipulation

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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