CVE-2026-103009: elastic elasticsearch

Vulnerability summary

CVE-2026-103009 is a high (CVSS 7.1) vulnerability in elastic elasticsearch. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.1% of scored vulnerabilities.

Timeline

1. 06-10-2026
   PublishedVulnerability first disclosed.
2. 06-10-2026
   Last modifiedVulnerability information updated.

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.

• CWE-639Authorization Bypass Through User-Controlled KeyThe system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.