Uncontrolled Recursion (CWE-674) in Elasticsearch can lead to Denial of Service via a specially crafted, deeply nested request submitted to the aggregation feature of the search API. Elasticsearch contains an uncontrolled recursion weakness in its search aggregation processing. An authenticated user with read access to a single index can submit a specially crafted request containing deeply nested aggregation definitions. Processing this request triggers unbounded recursive execution that exhausts the server process's available resources, causing the affected node to terminate. The node does not recover automatically and requires manual intervention to restore service.
Fix
Patch, vendor advisory and mitigation references on NVD 1
- https://discuss.elastic.co/t/elasticsearch-8-19-21-9-4-6-9-5-2-security-update-esa-2026-196/390870 Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 6.5 · elasticNVD modified 2026-10-09 13:26
Affected (CPE criteria) 1
cpe:2.3:a:elastic:elasticsearch:*:*:*:*:*:*:*:*