# CVE-2026-103009: Authorization Bypass Through User-Controlled Key in Elasticsearch Leading to Information Disclosure

> CVE-2026-103009: Authorization Bypass Through User-Controlled Key in Elasticsearch Leading to Information Disclosure. CVSS 7.1 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-103009
Last updated: 2026-10-09T13:13:05Z

- Published: 2026-10-06 19:31 UTC · Updated: 2026-10-09 13:13 UTC · Assigner: elastic
- CVSS: 7.1 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
- EPSS: 0.23%, 14th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-639

## Description

Authorization Bypass Through User-Controlled Key (CWE-639) in Elasticsearch can lead to Information Disclosure via a specially crafted cross-cluster search request that references an unauthorized shard identifier. Elasticsearch contains an authorization bypass weakness in its handling of cross-cluster search requests made through the Remote Cluster Security (RCS) 2.0 model. An authorization check validates a request against one identifying attribute of the target shard, while a separate, independently-supplied identifying attribute in the same request determines which shard is actually accessed. A holder of a cross-cluster API key authorized for one index can craft a request whose two identifying attributes refer to different indices, causing the request to be authorized against an index they can access while actually operating against a different, unauthorized index. This can expose that index's document contents, field mappings, and other metadata, and in limited cases allows modification of retention-lease state on the unauthorized index.

## Affected vendors and products

- Elastic: Elasticsearch

## Tracked companies

- [Elastic Cloud](https://rewindex.com/company/elastic-cloud.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-103009)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-103009)
- [https://discuss.elastic.co/t/elasticsearch-8-19-23-9-4-8-9-5-5-security-update-esa-2026-199/390874](https://discuss.elastic.co/t/elasticsearch-8-19-23-9-4-8-9-5-5-security-update-esa-2026-199/390874)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-103009 · Markdown: https://rewindex.com/cve/CVE-2026-103009.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-103009 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T04:06:16.962Z